Marie Davidova: Socio-Environmental Relations of Non-Discrete Spaces and Architectures

Socio-Environmental Relations of Non-Discrete Spaces and Architectures: Systemic Approach to Performative Wood

Marie Davidová, MArch. Founding Chair and Member of Collaborative Collective - PhD Research Fellow at FA CTU in Prague and FUA TU of Liberec - Scientific Consultant at Studio FLO|W, MOLAB department, FA CTU in Prague





This block of Douglas-�r was cut to show threeplanes: the transverse or cross-sectional surface (X), the radialsurface (R), and the tangential surface (T). (Photo by RandyO'Rourke) (Understanding Wood)

Both discs were cut from eastern redcedar trees.The sample on the left was shaded by the larger treesaround it reducing its crown. The one on the right grew normally in an open meadow with a full crown of foliageand greater need for sap conduction. (Understanding Wood)

Stem cross sections (top) and detail (bottom)show gross and �ne structures of a typical softwood, red pine(Pinus resinosa), and a typical hardwood, northern red oak(Quercus rubra). In red pine, narrow rays are t o o small to beseen without magni�cation, while portions of t he large rays inthe red oak are visible to the naked eye. (Photos by RandyO'Rourke) (understanding wood)

THE NATURE OF WOOD

ood comes from trees. This is the most importantfact to remember in understanding the nature ofwood. Whatever qualities or shortcomings wood

possesses are traceable to the tree whence it came. Woodevolved as a functional tissue of plants and not as a mate-rial designed to satisfy the needs of woodworkers. Thus,knowing wood as it grows in nature is basic to working suc-cessfully with it.

Since prehistoric times, man has used the beauty andeconomic value of trees in commerce and art as well as forshelter and furnishings, and one is tempted to discuss atlength the virtues of these noble representatives of the plantkingdom. But since our goal is to understand wood, we wil lconcentrate on the functional and physical aspects of treesrather than on their aesthetic aspects. We must consider thetree on a number of levels—from the entire plant down tothe individual cell.

At the microscopic level, understanding cell structure isthe key to appreciating what happens when wood is sandedacross the grain, why stain penetrates unevenly, and whyadhesives bleed through some veneers but not others. But tounderstand where feather grain is to be found, to visualize a knot's internal structure based on its surface appearance, andto anticipate which boards are susceptible to decay, it is nec-essary to examine the structure of the entire tree as a livingorganism (Figure 1.1). So this is a logical starting point.

Despite their wide diversity, all trees have certain com-mon characteristics (Figure 1.5). A l l are vascular, perennialplants capable of secondary thickening, or adding yearlygrowth to previous growth. The visible portion of the treehas a main supporting stem or trunk. If large enough forconversion into sawtimber or veneer, the trunk is oftentermed the bole. The trunk is the principal source of woodused by woodworkers, although pieces having unusualbeauty and utility also come from other parts of the tree. Thetrunk has limbs, which in turn branch and eventually subdi-vide into twigs. This subdivision, carrying the leaves orfoliage, is collectively termed the crown.

But a casual glance hardly reveals the awesome com-plexity of the internal structure of these impressive plants.One can begin an acquaintance by exposing a crosswise sur-face of a tree trunk (Figure 1.2). At the periphery of the log

RED PINE RED OAK

Figure 1.2 • Stem cross sections (top) and detail (bot tom)show gross and f ine structures of a typical so f twood, red pine(Pinus resinosa), and a typical hardwood, nor thern red oak(Quercus rubra). In red pine, narrow rays are t o o small to beseen w i t h o u t magni f icat ion, whi le por t ions of the large rays inthe red oak are visible to the naked eye. (Photos by RandyO'Rourke)

Bark

Sapwood

Pith

H e a r t w o o d

W

Outer(dead) bark

(l iving) bark

C a m b i u m

inner

RED PINE RED OAK

G r o w t h r ing

Grow th - r i ng

b o u n d a ry

Ear lywood

La tewood

Bark peels easily from summer-cut wood because the cambiallayer is fragile during the growing season. Bark is much harder to remove from wood cut during the dormant winter season. (Photo by Richard Starr) (Understanding Wood)

D e n d r i t i c form characteristic of hardwoods, left,contrasts w i th the excurrent f o rm typical of softwoods, right. (understanding Wood)

If spiral grain in a tree cycles one way and then theother, interlocked grain results. If a log from such a tree were turned down on a lathe, the reversing angle of the spiral grain would result as shown.(Understanding Wood)

Reaction wood forms in trees that lean (A). The curving sweep of this hemlock tree, although picturesque, means unpredictable compression wood will be found within as shown in the cross section (B). The section of spruce (C) shows severe compressive wood formation. (Photo A by R. Bruce Hoadley; photos B and C by Randy O'Rourke)(Understnding Wood)

As certain white rots develop, dark zone lines form, as on this piece of sugar maple (A).This type of decay is called spalting.(Understanding Wood)

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RED OAK (GREEN)

RED OAK (AIR-DRY)

RED OAK(OVEN-DRY)

Shrinkage vs. moisture content in northern red oak, a typical species.

It is reasonable to think of wood as having roughly 8% tangential shrinkage and 4% radial shrinkage. (Understanding Wood)

UNEVEN SHRINKAGE AND SWELLING - Warp (Understanding Wood)

A, illustration of a cut-away tree at various magni�cations, correspondingroughly with the images to its right; at the top, at an approximate magni�cationof 100×, a softwood cell and several hardwood cells are illustrated, to give a senseof scale between the two; one tier lower, at an approximate magni�cation of 50×, isa single growth ring of a softwood (left) and a hardwood (right), and an indication ofthe radial and tangential planes; the next tier, at approximately 5× magni�cation, illustratesmany growth rings together and how one might produce a straight-grainedrather than a diagonal-grained board; the lowest tier includes an illustration of therelative position of juvenile and mature wood in the tree, at 1× magni�cation. B,C, lightmicroscopic views of the lumina (L) and cell walls (arrowheads) of a softwood (B) anda hardwood (C). D,E, hand-lens views of growth rings, each composed of earlywood(ew) and latewood (lw), in a softwood (D) and a hardwood (E). F, a straight-grainedboard; note that the line along the edge of the board is parallel to the line along thegrain of the board. G, a diagonal-grained board; note that the two lines are markedlynot parallel; this board has a slope of grain of about 1 in 7. H, the gross anatomy of atree trunk, showing bark, sapwood, and heartwood. (Wood Handbook)

Strips were cut in sequence f r om the end of an air-dry red oak board. As shown by the middle strip, it measured 91/2 in. wide at 14% MC.The top strip was then dried to below 4% MC—it both shrinks and cups.The bottom strip was allowed to readsorb moisture to more than 20% MC. It expands and cups in the opposite direction. (Photo by Richard Starr)

Reaction wood is typically to blame when boards bow or crook, as in this piece of shiplap log-cabin siding (A). Reaction wood may also cause twisting, as shown in the Japanese �r (B). (Photo A by Richard Starr; photo B by Randy O'Rourke) (Understanding Wood)

Characteristic shrinkage and distortion of �at, square, and round pieces as a�ected by direction of growth rings. Tangential shrinkage is about twice as great as radial. (Wood Handbook)

The severity of cupping in a board is related to its position in the log. (Photo by R. Bruce Hoadley) (Understanding Wood)

Relationship of �ber orientation (O–O) to axes, as shown by schematic of wood specimens containing straight grain and cross grain. Specimens A through D have radial and tangential surfaces; E through H do not. Specimens A and E contain no cross grain; B, D, F, and H have spiral grain; C, D, G, and H have diagonal grain. (Wood Handbook)

Properties of juvenile wood.

Mold and stain fungi do not seriously a�ect most mechanicalproperties of wood because such fungi feed on substanceswithin the cell cavity or attached to the cell wall ratherthan on the structural wall itself. The duration of infectionand the species of fungi involved are important factors indetermining the extent of degradation. (Wood Handbook)

A simple water drop test shows di�erences in wettability of yellow birch veneer surface. Three drops were applied to surface simultaneously and then photographed after 30 s. Left drop retained a large contact angle on aged and unsanded surface; center drop had a smaller contact angle and improved wettability after the surface was renewed by two passes with 320-grit sandpaper; right drop showed a small contact angle and good wettability after four passes with the sandpaper. (Wood Handbook)

Representative samples of four common types of fungal growth on wood: (a) mold discoloration; (b) brown rotted pine (note the darkcolor and cubical checking in the wood); (c) white rot in maple (note the bleached appearance); (d) softrotted preservative-treated pine utility pole (note the shallow depth of decay).

Unlike mold and stain fungi, wood-destroying (decay) fungiseriously reduce strength by metabolizing the cellulose fractionof wood that gives wood its strength. (Wood Handbook)

Artist’s rendition of weathering process of round and square timbers. As cutaway shows, interior wood below surface is relatively unchanged. (Wood Handbook)

Blue-stained wood of alder (Alnus glutnosa) naturally colonised by the blue pigmented hyphae of Chlorosplenium aeruginascens. This type of coloration is quite common in fallen branches of alder and oak. (Jim Deacon)

Composite Veneer Plate Responding to Changes in Relative Humidity (Performative Wood)

The amount of bound water in wood is determined by the relative humidity (RH) of t he surrounding atmosphere; the amount of bound water changes as the RH changes.The moisture content of the wood when a balance is established at a given RH is its equilibrium moisture content (EMC).The solid line on the graph represents the relationship between EMC and RH for white spruce, a typical species with a �ber saturation point (FSP) o f about 3 0 % EMC. It is a fair approximation o f the relationship for most common woods. (Understanding Wood)

Wood always remains hygroscopic, which means that itresponds to changes in atmospheric humidity. As the RHdrops, it loses bound water; as the RH increases, the woodregains bound water. For a given RH level, a balance is eventuallyreached at which the wood is no longer gaining or losingmoisture. When this balance of moisture exchange isestablished, the amount of bound water eventually containedin a piece of wood is called the equilibrium moisture content(EMC) of the wood. (Understanding Wood)

Now imagine thoroughly wringing out the wet spongeuntil no further water is evident. The sponge remains fullsized,�exible, and damp to the touch. In wood, the comparablecondition is called the �ber saturation point (FSP).In this state, the cell cavities are emptied of free water, butthe cell walls are still saturated and thus still in their weakestcondition. Only when water leaves the cell walls does thewood begin to shrink and increase in strength.(Understanding Wood)

It is important to realize that if the absolute humidity of air is unchanged, lowering the temperature of the air raises the RH, while heating the air lowers the RH. (Understanding Wood)

4–3

Chapter 4 Moisture Relations and Physical Properties of Wood

one portion all cell lumina may be empty and the cell walls partially dried, while in another part of the same piece, cell walls may be saturated and lumina partially or completely

begin to dry before all water has left the lumen of that same cell.

The moisture content at which both cell lumina and cell walls are completely saturated with water is the maximum

Gb (based on ovendry mass and green volume—see section on Density

gravity of wood cell walls is constant among species. This decreases the maximum moisture content because less room is available for free water. Maximum moisture content MCmax

(4–3)

1.54. Maximum possible moisture content varies from 267% at Gb = 0.30 to 44% at Gb = 0.90. Maximum possible mois-ture content is seldom attained in living trees. The moisture content at which wood will sink in water can be calculated by

(4–4)

Water Vapor SorptionWhen wood is protected from contact with liquid water and

saturation point is a function of both relative humidity (RH) and temperature of the surrounding air. Wood in service is exposed to both long-term (seasonal) and short-term (daily) changes in relative humidity and temperature of the surrounding air, which induce changes in wood moisture content. These changes usually are gradual, and short-term

-ture content changes can be retarded, but not prevented, by protective coatings such as varnish, lacquer, or paint

product will have in service (Chap. 13).

Equilibrium Moisture Content-

ture content at which the wood is neither gaining nor losing moisture. The relationship between EMC, relative humidity, and temperature is shown in Figure 4–1 and Table 4–2. For most practical purposes, the values in Table 4–2 may be ap-plied to wood of any species. These values have been calcu-lated from the following equation:

(4–5)

where h is relative humidity (decimal) and the parameters W, K, K1, and K2 depend on temperature:

For temperature T in °C, W = 349 + 1.29T + 0.0135T2

K = 0.805 + 0.000736T 0.00000273T2

K1 = 6.27 0.00938T 0.000303T2 K2 = 1.91 + 0.0407T 0.000293T2

For temperature T in °F, W = 330 + 0.452T + 0.00415T 2 K = 0.791 + 0.000463T 0.000000844T2

K1 = 6.34 + 0.000775T 0.0000935T2

K2 = 1.09 + 0.0284T 0.0000904T2

Simpson (1973) showed that this equation provides a good

Sorption HysteresisThe relationship between EMC and relative humidity at constant temperature is referred to as a sorption isotherm. The history of a wood specimen also affects its EMC; this is called sorption hysteresis and is shown in Figure 4–2. A desorption isotherm is measured by bringing wood that was initially wet to equilibrium with successively lower values of relative humidity. A resorption, or adsorption, isotherm is measured in the opposite direction (from the dry state to successively higher RH values). As wood is dried from

(initial desorption), the EMC is greater than in subsequent desorption isotherms (Spalt 1958). Furthermore, the EMC

10 20 30 40 50 60 70 80 90

10

20

30

40

50

60

70

80

90

100

Relative humidity (%)

Tem

pera

ture

(ºC

)

2 4 6 8 10 12 14 16 20 24

Figure 4–1. Equilibrium moisture content of wood (la-beled contours) as a function of relative humidity and temperature.

Equilibrium moisture content of wood (labeled contours) as a function of relative humidity and temperature. (Wood Handbook)

Humidity

Bow

Twist

Diamonding

Crook

Kink

Wood

červenecleden

hory

nížiny

rok

RHReaction wood in tangential section warps in unexpected directions within the same humidity conditions. More than half of the samples bends the opposite direction. The same occurance has been opserved in regullar pine wood in one from ten samples. This behaviour latter disappeared.

A fence covered by algae was observed.The wood with algae has approximately from two to four lower percentage of moisture content than the wood without it.This feature can be used in relation to wood warping.

Samples of Apatococcus and Klebsormidium were grown on ash, false acacia and pine wood samples. While Apatococcus is growing qite well, Klebsormidium died after certain time. The best succes was on ash wood followed by false acacia and than pine wood.

Four types of samples were observed on regullar green and dry wood: rectangular shape, parallelogram, rhombus and rect-angle with notches. There was not so much difference between green and dry wood. The rhombus shape was bending the most, continued with parallelogram and after that rectangle. The rhombus bends into 2cm difference, the rectangle 1cm on 30cm wide plate.

The rectangle with notches was at the begining not warping at all and latter on bended into a state where it stays not in dependancy on relative humidity.

False acacia reaction wood

Pineregullar wood

Fence with algaeNové Město nad Metují

ApatococcusKlebsormidium

different direction of warping in reaction w

oodwood w

arping in relation to shape - 10% R

H, 21°C

moisture content in relation to algae appereance

growth of algae in relation to different species of w

ood

1 cm

0%

3%

2 cm

Environmental Pavilion Concept

The pavilion reacts to relative hu-midity by warping it’s wings in the opposite direction. Thanks to that, the pavilion closes when it’s humid and opens when dry weather. The concept of the opposite fibre ori-entation it tangential section was further developped into different performative systems proposals.

00_Movable Wall Concept


02_Performative Sunshading Concept

03_Performative Facade Concept





08_Concept Sponge

09_Concept Ray

Concept Sponge

The performative fasade con-cept is generating 1 cm² holl per 10 cm² area of the pan-elling.The panells are interdepen-dent

Concept Ray

The performative fasade con-cept is generating 1 cm² holl per 7,2 cm² area of the panelling.The panells are not interde-pendent.

System Ray2

Concept Ray was developed further for the protection from rain. It is based on the fact that the plates from the center of tree trunk warp more than the others. The system is generating 1 cm² holl per 7,8 cm² area of the panelling.

Folding of the plates is arranged so, that they create three layers which lead the rain water down from the system.

Based on the discussion with the producer a supportive system was developed so, taht its parts are dif-ficult to produce and nor easy to copy.

The working prototype

Prototype model

Design Process

Spruce 43,2%, 40 119 836 m³

The main problem is generally seen that the area is suffering with spruce monocultures that are not natural in low lands. Spruce wood is mainly preferred by the market for its fast growth thus fast income. No matter that conifers' wood from low lands have low quality in strength (Coulson, 2012). I don't see the biggest prob-lem of Central Bohemia in spruce monocultures for the reason that they are subject to natural succession and they will disappear while they are not artificially grown.

Silver Fir 0,8%, 40 758 847 m³

Is natural in highlands.

Pine 21,8%, 20 243 162 m³

Petr Pokorný in his pollen analysis proves high occurrence of pine forests all over the history. (Pokorný, 2011) Pine forests naturally grow in the lo-cations with low level of nutrients. (Němec & Hrib, 2009).

False Acacia 0,8%, 747 916 m³

The urgent problem are the monocul-tures of false acacia. The false acacia is coming from Asia and even though it's taking only 0,8% of existing forests and it spreads fast by producing chemicals that are killing the existing ecosystems.

Larch 6,7%, 6 173 639 m³

Other Broadleaves 0,4%, 340 563 m³

Willow 0,4%, 387 859 m³

Poplar 0,6%, 542 315 m³

Aspen 0,4%, 331 618 m³

Lime 1,0%, 959 284 m³

Alder 1,6%, 1 521 987 m³

Birch 2,0%, 1 869 535 m³

Elm 0,1%, 83 242 m³

Ash 1,3%, 1 207 699 m³

Maple 0,9%, 871 975 m³

Hornbeam 1,5%, 1 418 096 m³

Beech 4,5%, 4 131 535 m³

Red Oak 0,6%, 574 585 m³

Oak 11,0%, 10 170 053 m³

Douglas Fir 0,4%, 347 847 m³

Forests of Central Bohemia

babykasesychá:

tangenciálně: 2,97 - 7,9%radiálně: 2,03 - 5,45%podélně: 0,4%

nabývá:

tangenciálně: 6,59%radiálně: 3,35%podélně: 0,072%na váze: 71 - 79%

v teple snadno praská a bortí se

tvrdost:

IV. tvrdé

pružnost a pevnost:

neobyčejně houževnaté, tuhé a pevné

trvanlivost:

v suchu trvanlivé

borovice černásesychá:


nabývá:

tangenciálně: %radiálně: %podélně: %na váze: %

tvrdost:

I. velmi měkké


velmi pružné, pevné skoro jako mořín

trvanlivost:

velmi trvanlivé ve vodě, v suchu i střídání vlhkosti

borovice vejmutovkasesychá:

tangenciálně: 1,3 - 5%radiálně: 0,2 - 2,7%podélně: 0,04 - 0,16%

nabývá:

tangenciálně: 5%radiálně: 1,8%podélně: 0,16%na váze: %

tvrdost:

I. velmi měkké


málo pružné a pevné

trvanlivost:

málo trvanlivé, dřevo strších stromů trvanlivější

borovice obecná (sosna)sesychá:

tangenciálně: 2,0 - 6,8%radiálně: 0,6 - 3,8%podélně: 0,008 - 0,201%

nabývá:

tangenciálně: 5,72%radiálně: 3,04%podélně: 0,12%na váze: %

tvrdost:

I. velmi měkké


poměrně pružné a velmi pevné

trvanlivost:

velmi trvanlivé ve vodě, méně na suchu

břek (břekyně)sesychá:


nabývá:


vyschlé dřevo nepraská a nebortí se

tvrdost:

IV. tvrdé


pevné, pružné , ohebné, velmi houževnaté

trvanlivost:

velmi trvanlivé

bříza bílá - obecnásesychá:


nabývá:

tangenciálně: 9,3%radiálně: 3,68%podélně: 0,222%na váze: 91 -97%

tvrdost:

II. měkké


pevné, ohebné, houževnaté v kroucení

trvanlivost:

ve vlhku a v zemi málo trvanlivé, v suchu víc

buk lesnísesychá:

tangenciálně: 5 - 10,7%radiálně: 2,3 - 6%podélně: 0,2 - 0,34%

nabývá:

tangenciálně: 8,06%radiálně: 5,03%podélně: %na váze: 63 -99%

dlouho silně pracuje, praská, chytá houby

tvrdost:

VI. tvrdé


pevné, málo pružné, napařené je ohebné

trvanlivost:

pod vodou a v suchu trvanlivé, jinak ne

dubsesychá:


nabývá:


praská, suší se v kůře a dlouho

tvrdost:

VI. tvrdé


velmi pevné a pružné, z mladých stromů houževnaté

trvanlivost:

nejtrvanlivější z evropských dřevin v suchu i vlhku

habr obecnýsesychá:


nabývá:

tangenciálně: 10,9%radiálně: 6,66%podélně: 0,4%na váze: 60%

vysychá pomalu a nerovnoměrně, bortí se a praská

tvrdost:

VI. tvrdé


trvanlivost:

málo trvanlivé, vydrží dlouho jen ve stálém suchu

hrušeň obecnásesychá:

tangenciálně: 5,5 - 6%radiálně: 2,9 - 3,94%podélně: 0,228%

nabývá:


nebortí se

tvrdost:

VI. tvrdé


málo pružné, dost ohebné, tuhé, pevné, houževnaté

trvanlivost:

velmi trvanlivé, především v suchu

jabloň obecnásesychá:

tangenciálně: 5,7 - 9%radiálně: 3,1 - 6%podélně: 0,109%

nabývá:

tangenciálně: 7,39%radiálně: 3%podélně: 0,109%na váze: 86%

značně se bortí a praská

tvrdost:

VI. tvrdé


pevné, málo pružné

trvanlivost:

málo trvanlivé

jalovec obecnýsesychá:

tangenciálně: 2,3%radiálně: 1,3%podélně: 0,17%

nabývá:


ohrožený druh

tvrdost:

II. měkké


velmi pevné a tuhé, houževnaté (hl. od kořenů)

trvanlivost:

velmi na volném vzduchu i v uzavřeném prostoru

jasan ztepilýsesychá:


nabývá:


velmi málo se bortí a praská

tvrdost:

IV. tvrdé


pevné, velmi pružné, ohebné a houževnaté

trvanlivost:

venku a v zemi málo trvanlivé, v suchu trvanlivé

javor klensesychá:

tangenciálně: 4,13 - 7,3%radiálně: 2 - 5,4%podélně: 0,062 - 0,2%

nabývá:


v teple se bortí a praská

tvrdost:

IV. tvrdé


pevné, velmi pružné a houževnaté

trvanlivost:

venku málo trvanlivé, v suchu trvanlivé

javor mléčnýsesychá:


nabývá:



tvrdost:

IV. tvrdé


velmi pevné, pružné a houževnaté (h. víc než klen)

trvanlivost:

trvanlivé pouze v suchu

jedle bělokorásesychá:

tangenciálně: 2,4%radiálně: 1,9%podélně: 0,086 - 0,12%

nabývá:


tvrdost:

I. velmi měkké


velmi pružné, málo ohebné

trvanlivost:

v suchu a pod vodou, porušuje se při kolísání vlhkosti

jilm polnísesychá:


nabývá:


značně praská - musí se pomalu sušit

tvrdost:

III. středně tvrdé


pevné, pružné, houževnaté

trvanlivost:

velmi trvanlivé, nejvíce v trvalém vlhku nebo suchu

jírovec maďal - kaštansesychá:

tangenciálně: 6,5 - 9,7%radiálně: 1,84 - 3%podélně: 0,08%

nabývá:


málo se bortí

tvrdost:

I. velmi měkké


málo pružné, velmi ohebné

trvanlivost:

velmi málo trvanlivé, upotřebitelné jen v suchu

jíva rokytkasesychá:


nabývá:


tvrdost:

II. měkké


pružné, ohebné a houževnaté

trvanlivost:

málo trvanlivé, podléhá hnilobě jádra

lípa malolistásesychá:

tangenciálně: 8 - 10%radiálně: 1 - 7%podélně: %

nabývá:


praská, suché dřevo se nebortí a nepraská

tvrdost:

I. velmi měkké


málo pružné, ohebné a houževnaté

trvanlivost:

trvanlivé jen v suchu

modřín evropskýsesychá:


nabývá:


málo se bortí

tvrdost:

II. měkké


velmi pružné a pevné

trvanlivost:

nejvíce z jehličňanů, pod vodou rychle tvrdne

muk obecnýsesychá:

tangenciálně: 7,23 - 11,5%radiálně: 3,9 - 10%podélně: %

nabývá:


silně sesychá a praská, nebortí se

tvrdost:

IV. tvrdé


velmi pevné, houževnaté

trvanlivost:

velmi trvanlivé

olše černá, lepkavásesychá:


nabývá:


tvrdost:

II. měkké


málo pevné a pružné, křehké a lámavé

trvanlivost:

velmi pod vodou, lepší na suchu, nesnáší kulm. vlhkosti

ořešák vlašskýsesychá:

tangenciálně: 4 - 17,6%radiálně: 2,6 - 8,2%podélně: 0,223%

nabývá:


vyschlé dřevo se nebortí a nepraská

tvrdost:

IV. tvrdé


málo pružné a ohebné, tuhé

trvanlivost:

velmi, ale blána se brzy kazí

osikasesychá:


nabývá:


tvrdost:

I. velmi měkké


pružné a pevné

trvanlivost:

v suchu trvanlivé

platan západnísesychá:


nabývá:


snadno bobtná, silně pracuje

tvrdost:



trvanlivost:

málo trvanlivé

smrk obecný, ztepilýsesychá:


nabývá:


tvrdost:

I. velmi měkké


z našich dřev nejpružnější a nejpevnější

trvanlivost:

poměrně dobrá

švestkasesychá:


nabývá:


tvrdost:

IV. tvrdé


křehké v lomu, silně praská

trvanlivost:

malá, hlavně venku, v suchu červotočina

tissesychá:

tangenciálně: 2,6 - 4%radiálně: 2,4 - 2,9%podélně: %

nabývá:


silně ohrožený, dřevo výstředně rostlé

tvrdost:

IV. tvrdé, nejtvrdší z našich jehličňanů


velmi tuhé, pružné a houževnaté

trvanlivost:

velmi trvanlivé

třešeňsesychá:


nabývá:


tvrdost:

IV. tvrdé


pevné, ohebné a pružné

trvanlivost:

málo trvanlivé, běl se nepoužívá

trnovník akátsesychá:


nabývá:


tvrdost:

IV. tvrdé


pevné, pružné, velmi ohebné

trvanlivost:

neobyčejně trvanlivé za všech poměrů

IV. hard

III. semihard<<< shrinks does not shrink >>>

II. soft

I. very softWood Shrinkage


This block of Douglas-�r was cut to show threeplanes: the transverse or cross-sectional surface (X), the radialsurface (R), and the tangential surface (T). (Photo by RandyO'Rourke) (Understanding Wood)

Both discs were cut from eastern redcedar trees.The sample on the left was shaded by the larger treesaround it reducing its crown. The one on the right grew normally in an open meadow with a full crown of foliageand greater need for sap conduction. (Understanding Wood)

Stem cross sections (top) and detail (bottom)show gross and �ne structures of a typical softwood, red pine(Pinus resinosa), and a typical hardwood, northern red oak(Quercus rubra). In red pine, narrow rays are t o o small to beseen without magni�cation, while portions of t he large rays inthe red oak are visible to the naked eye. (Photos by RandyO'Rourke) (understanding wood)

THE NATURE OF WOOD

ood comes from trees. This is the most importantfact to remember in understanding the nature ofwood. Whatever qualities or shortcomings wood

possesses are traceable to the tree whence it came. Woodevolved as a functional tissue of plants and not as a mate-rial designed to satisfy the needs of woodworkers. Thus,knowing wood as it grows in nature is basic to working suc-cessfully with it.

Since prehistoric times, man has used the beauty andeconomic value of trees in commerce and art as well as forshelter and furnishings, and one is tempted to discuss atlength the virtues of these noble representatives of the plantkingdom. But since our goal is to understand wood, we wil lconcentrate on the functional and physical aspects of treesrather than on their aesthetic aspects. We must consider thetree on a number of levels—from the entire plant down tothe individual cell.

At the microscopic level, understanding cell structure isthe key to appreciating what happens when wood is sandedacross the grain, why stain penetrates unevenly, and whyadhesives bleed through some veneers but not others. But tounderstand where feather grain is to be found, to visualize a knot's internal structure based on its surface appearance, andto anticipate which boards are susceptible to decay, it is nec-essary to examine the structure of the entire tree as a livingorganism (Figure 1.1). So this is a logical starting point.

Despite their wide diversity, all trees have certain com-mon characteristics (Figure 1.5). A l l are vascular, perennialplants capable of secondary thickening, or adding yearlygrowth to previous growth. The visible portion of the treehas a main supporting stem or trunk. If large enough forconversion into sawtimber or veneer, the trunk is oftentermed the bole. The trunk is the principal source of woodused by woodworkers, although pieces having unusualbeauty and utility also come from other parts of the tree. Thetrunk has limbs, which in turn branch and eventually subdi-vide into twigs. This subdivision, carrying the leaves orfoliage, is collectively termed the crown.

But a casual glance hardly reveals the awesome com-plexity of the internal structure of these impressive plants.One can begin an acquaintance by exposing a crosswise sur-face of a tree trunk (Figure 1.2). At the periphery of the log

RED PINE RED OAK

Figure 1.2 • Stem cross sections (top) and detail (bot tom)show gross and f ine structures of a typical so f twood, red pine(Pinus resinosa), and a typical hardwood, nor thern red oak(Quercus rubra). In red pine, narrow rays are t o o small to beseen w i t h o u t magni f icat ion, whi le por t ions of the large rays inthe red oak are visible to the naked eye. (Photos by RandyO'Rourke)

Bark

Sapwood

Pith

H e a r t w o o d

W

Outer(dead) bark

(l iving) bark

C a m b i u m

inner

RED PINE RED OAK

G r o w t h r ing

Grow th - r i ng

b o u n d a r y

Ear lywood

La tewood

Bark peels easily from summer-cut wood because the cambiallayer is fragile during the growing season. Bark is much harder to remove from wood cut during the dormant winter season. (Photo by Richard Starr) (Understanding Wood)

D e n d r i t i c form characteristic of hardwoods, left,contrasts w i th the excurrent f o rm typical of softwoods, right. (understanding Wood)

If spiral grain in a tree cycles one way and then theother, interlocked grain results. If a log from such a tree were turned down on a lathe, the reversing angle of the spiral grain would result as shown.(Understanding Wood)

Reaction wood forms in trees that lean (A). The curving sweep of this hemlock tree, although picturesque, means unpredictable compression wood will be found within as shown in the cross section (B). The section of spruce (C) shows severe compressive wood formation. (Photo A by R. Bruce Hoadley; photos B and C by Randy O'Rourke)(Understnding Wood)

As certain white rots develop, dark zone lines form, as on this piece of sugar maple (A).This type of decay is called spalting.(Understanding Wood)

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RED OAK (GREEN)

RED OAK (AIR-DRY)

RED OAK(OVEN-DRY)

Shrinkage vs. moisture content in northern red oak, a typical species.

It is reasonable to think of wood as having roughly 8% tangential shrinkage and 4% radial shrinkage. (Understanding Wood)

UNEVEN SHRINKAGE AND SWELLING - Warp (Understanding Wood)

A, illustration of a cut-away tree at various magni�cations, correspondingroughly with the images to its right; at the top, at an approximate magni�cationof 100×, a softwood cell and several hardwood cells are illustrated, to give a senseof scale between the two; one tier lower, at an approximate magni�cation of 50×, isa single growth ring of a softwood (left) and a hardwood (right), and an indication ofthe radial and tangential planes; the next tier, at approximately 5× magni�cation, illustratesmany growth rings together and how one might produce a straight-grainedrather than a diagonal-grained board; the lowest tier includes an illustration of therelative position of juvenile and mature wood in the tree, at 1× magni�cation. B,C, lightmicroscopic views of the lumina (L) and cell walls (arrowheads) of a softwood (B) anda hardwood (C). D,E, hand-lens views of growth rings, each composed of earlywood(ew) and latewood (lw), in a softwood (D) and a hardwood (E). F, a straight-grainedboard; note that the line along the edge of the board is parallel to the line along thegrain of the board. G, a diagonal-grained board; note that the two lines are markedlynot parallel; this board has a slope of grain of about 1 in 7. H, the gross anatomy of atree trunk, showing bark, sapwood, and heartwood. (Wood Handbook)

Strips were cut in sequence f r om the end of an air-dry red oak board. As shown by the middle strip, it measured 91/2 in. wide at 14% MC.The top strip was then dried to below 4% MC—it both shrinks and cups.The bottom strip was allowed to readsorb moisture to more than 20% MC. It expands and cups in the opposite direction. (Photo by Richard Starr)

Reaction wood is typically to blame when boards bow or crook, as in this piece of shiplap log-cabin siding (A). Reaction wood may also cause twisting, as shown in the Japanese �r (B). (Photo A by Richard Starr; photo B by Randy O'Rourke) (Understanding Wood)

Characteristic shrinkage and distortion of �at, square, and round pieces as a�ected by direction of growth rings. Tangential shrinkage is about twice as great as radial. (Wood Handbook)

The severity of cupping in a board is related to its position in the log. (Photo by R. Bruce Hoadley) (Understanding Wood)

Relationship of �ber orientation (O–O) to axes, as shown by schematic of wood specimens containing straight grain and cross grain. Specimens A through D have radial and tangential surfaces; E through H do not. Specimens A and E contain no cross grain; B, D, F, and H have spiral grain; C, D, G, and H have diagonal grain. (Wood Handbook)

Properties of juvenile wood.

Mold and stain fungi do not seriously a�ect most mechanicalproperties of wood because such fungi feed on substanceswithin the cell cavity or attached to the cell wall ratherthan on the structural wall itself. The duration of infectionand the species of fungi involved are important factors indetermining the extent of degradation. (Wood Handbook)

A simple water drop test shows di�erences in wettability of yellow birch veneer surface. Three drops were applied to surface simultaneously and then photographed after 30 s. Left drop retained a large contact angle on aged and unsanded surface; center drop had a smaller contact angle and improved wettability after the surface was renewed by two passes with 320-grit sandpaper; right drop showed a small contact angle and good wettability after four passes with the sandpaper. (Wood Handbook)

Representative samples of four common types of fungal growth on wood: (a) mold discoloration; (b) brown rotted pine (note the darkcolor and cubical checking in the wood); (c) white rot in maple (note the bleached appearance); (d) softrotted preservative-treated pine utility pole (note the shallow depth of decay).

Unlike mold and stain fungi, wood-destroying (decay) fungiseriously reduce strength by metabolizing the cellulose fractionof wood that gives wood its strength. (Wood Handbook)

Artist’s rendition of weathering process of round and square timbers. As cutaway shows, interior wood below surface is relatively unchanged. (Wood Handbook)

Blue-stained wood of alder (Alnus glutnosa) naturally colonised by the blue pigmented hyphae of Chlorosplenium aeruginascens. This type of coloration is quite common in fallen branches of alder and oak. (Jim Deacon)

Composite Veneer Plate Responding to Changes in Relative Humidity (Performative Wood)

The amount of bound water in wood is determined by the relative humidity (RH) of t he surrounding atmosphere; the amount of bound water changes as the RH changes.The moisture content of the wood when a balance is established at a given RH is its equilibrium moisture content (EMC).The solid line on the graph represents the relationship between EMC and RH for white spruce, a typical species with a �ber saturation point (FSP) o f about 3 0 % EMC. It is a fair approximation o f the relationship for most common woods. (Understanding Wood)

Wood always remains hygroscopic, which means that itresponds to changes in atmospheric humidity. As the RHdrops, it loses bound water; as the RH increases, the woodregains bound water. For a given RH level, a balance is eventuallyreached at which the wood is no longer gaining or losingmoisture. When this balance of moisture exchange isestablished, the amount of bound water eventually containedin a piece of wood is called the equilibrium moisture content(EMC) of the wood. (Understanding Wood)

Now imagine thoroughly wringing out the wet spongeuntil no further water is evident. The sponge remains fullsized,�exible, and damp to the touch. In wood, the comparablecondition is called the �ber saturation point (FSP).In this state, the cell cavities are emptied of free water, butthe cell walls are still saturated and thus still in their weakestcondition. Only when water leaves the cell walls does thewood begin to shrink and increase in strength.(Understanding Wood)

It is important to realize that if the absolute humidity of air is unchanged, lowering the temperature of the air raises the RH, while heating the air lowers the RH. (Understanding Wood)

4–3


one portion all cell lumina may be empty and the cell walls partially dried, while in another part of the same piece, cell walls may be saturated and lumina partially or completely

begin to dry before all water has left the lumen of that same cell.

The moisture content at which both cell lumina and cell walls are completely saturated with water is the maximum

Gb (based on ovendry mass and green volume—see section on Density

gravity of wood cell walls is constant among species. This decreases the maximum moisture content because less room is available for free water. Maximum moisture content MCmax

(4–3)

1.54. Maximum possible moisture content varies from 267% at Gb = 0.30 to 44% at Gb = 0.90. Maximum possible mois-ture content is seldom attained in living trees. The moisture content at which wood will sink in water can be calculated by

(4–4)

Water Vapor SorptionWhen wood is protected from contact with liquid water and

saturation point is a function of both relative humidity (RH) and temperature of the surrounding air. Wood in service is exposed to both long-term (seasonal) and short-term (daily) changes in relative humidity and temperature of the surrounding air, which induce changes in wood moisture content. These changes usually are gradual, and short-term

-ture content changes can be retarded, but not prevented, by protective coatings such as varnish, lacquer, or paint

product will have in service (Chap. 13).

Equilibrium Moisture Content-

ture content at which the wood is neither gaining nor losing moisture. The relationship between EMC, relative humidity, and temperature is shown in Figure 4–1 and Table 4–2. For most practical purposes, the values in Table 4–2 may be ap-plied to wood of any species. These values have been calcu-lated from the following equation:

(4–5)



K = 0.805 + 0.000736T 0.00000273T2

K1 = 6.27 0.00938T 0.000303T2 K2 = 1.91 + 0.0407T 0.000293T2

For temperature T in °F, W = 330 + 0.452T + 0.00415T 2 K = 0.791 + 0.000463T 0.000000844T2

K1 = 6.34 + 0.000775T 0.0000935T2

K2 = 1.09 + 0.0284T 0.0000904T2

Simpson (1973) showed that this equation provides a good

Sorption HysteresisThe relationship between EMC and relative humidity at constant temperature is referred to as a sorption isotherm. The history of a wood specimen also affects its EMC; this is called sorption hysteresis and is shown in Figure 4–2. A desorption isotherm is measured by bringing wood that was initially wet to equilibrium with successively lower values of relative humidity. A resorption, or adsorption, isotherm is measured in the opposite direction (from the dry state to successively higher RH values). As wood is dried from

(initial desorption), the EMC is greater than in subsequent desorption isotherms (Spalt 1958). Furthermore, the EMC

10 20 30 40 50 60 70 80 90

10

20

30

40

50

60

70

80

90

100


Tem

pera

ture

(ºC

)

2 4 6 8 10 12 14 16 20 24


Equilibrium moisture content of wood (labeled contours) as a function of relative humidity and temperature. (Wood Handbook)

Humidity

Bow

Twist

Diamonding

Crook

Kink

Wood

červenecleden

hory

nížiny

rok

RHReaction wood in tangential section warps in unexpected directions within the same humidity conditions. More than half of the samples bends the opposite direction. The same occurance has been opserved in regullar pine wood in one from ten samples. This behaviour latter disappeared.

A fence covered by algae was observed.The wood with algae has approximately from two to four lower percentage of moisture content than the wood without it.This feature can be used in relation to wood warping.

Samples of Apatococcus and Klebsormidium were grown on ash, false acacia and pine wood samples. While Apatococcus is growing qite well, Klebsormidium died after certain time. The best succes was on ash wood followed by false acacia and than pine wood.

Four types of samples were observed on regullar green and dry wood: rectangular shape, parallelogram, rhombus and rect-angle with notches. There was not so much difference between green and dry wood. The rhombus shape was bending the most, continued with parallelogram and after that rectangle. The rhombus bends into 2cm difference, the rectangle 1cm on 30cm wide plate.

The rectangle with notches was at the begining not warping at all and latter on bended into a state where it stays not in dependancy on relative humidity.

False acacia reaction wood

Pineregullar wood

Fence with algaeNové Město nad Metují

ApatococcusKlebsormidium

different direction of warping in reaction w

oodwood w

arping in relation to shape - 10% R

H, 21°C

moisture content in relation to algae appereance

growth of algae in relation to different species of w

ood

1 cm

0%

3%

2 cm

Environmental Pavilion Concept

The pavilion reacts to relative hu-midity by warping it’s wings in the opposite direction. Thanks to that, the pavilion closes when it’s humid and opens when dry weather. The concept of the opposite fibre ori-entation it tangential section was further developped into different performative systems proposals.



02_Performative Sunshading Concept






08_Concept Sponge

09_Concept Ray

Concept Sponge

The performative fasade con-cept is generating 1 cm² holl per 10 cm² area of the pan-elling.The panells are interdepen-dent

Concept Ray

The performative fasade con-cept is generating 1 cm² holl per 7,2 cm² area of the panelling.The panells are not interde-pendent.

System Ray2

Concept Ray was developed further for the protection from rain. It is based on the fact that the plates from the center of tree trunk warp more than the others. The system is generating 1 cm² holl per 7,8 cm² area of the panelling.

Folding of the plates is arranged so, that they create three layers which lead the rain water down from the system.

Based on the discussion with the producer a supportive system was developed so, taht its parts are dif-ficult to produce and nor easy to copy.

The working prototype

Prototype model

Design Process

Spruce 43,2%, 40 119 836 m³


Silver Fir 0,8%, 40 758 847 m³


Pine 21,8%, 20 243 162 m³




Larch 6,7%, 6 173 639 m³


Willow 0,4%, 387 859 m³

Poplar 0,6%, 542 315 m³

Aspen 0,4%, 331 618 m³

Lime 1,0%, 959 284 m³

Alder 1,6%, 1 521 987 m³

Birch 2,0%, 1 869 535 m³

Elm 0,1%, 83 242 m³

Ash 1,3%, 1 207 699 m³

Maple 0,9%, 871 975 m³

Hornbeam 1,5%, 1 418 096 m³

Beech 4,5%, 4 131 535 m³

Red Oak 0,6%, 574 585 m³

Oak 11,0%, 10 170 053 m³

Douglas Fir 0,4%, 347 847 m³

Forests of Central Bohemia

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II. soft

I. very softWood Shrinkage


Spruce 43,2%, 40 119 836 m³


Silver Fir 0,8%, 40 758 847 m³


Pine 21,8%, 20 243 162 m³




Larch 6,7%, 6 173 639 m³


Willow 0,4%, 387 859 m³

Poplar 0,6%, 542 315 m³

Aspen 0,4%, 331 618 m³

Lime 1,0%, 959 284 m³



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4–3


one portion all cell lumina may be empty and the cell walls partially dried, while in another part of the same piece, cell walls may be saturated and lumina partially or completely filled with water. Even within a single cell, the cell wall may begin to dry before all water has left the lumen of that same cell.

The moisture content at which both cell lumina and cell walls are completely saturated with water is the maximum possible moisture content. Basic specific gravity Gb (based on ovendry mass and green volume—see section on Density and Specific Gravity) is the major determinant of maximum moisture content. As basic specific gravity increases, the volume of the lumina must decrease because the specific gravity of wood cell walls is constant among species. This decreases the maximum moisture content because less room is available for free water. Maximum moisture content MCmax for any basic specific gravity can be estimated from

(4–3)

where the specific gravity of wood cell walls is taken as 1.54. Maximum possible moisture content varies from 267% at Gb = 0.30 to 44% at Gb = 0.90. Maximum possible mois-ture content is seldom attained in living trees. The moisture content at which wood will sink in water can be calculated by

(4–4)

Water Vapor SorptionWhen wood is protected from contact with liquid water and shaded from sunlight, its moisture content below the fiber

saturation point is a function of both relative humidity (RH) and temperature of the surrounding air. Wood in service is exposed to both long-term (seasonal) and short-term (daily) changes in relative humidity and temperature of the surrounding air, which induce changes in wood moisture content. These changes usually are gradual, and short-term fluctuations tend to influence only the wood surface. Mois-ture content changes can be retarded, but not prevented, by protective coatings such as varnish, lacquer, or paint (Chap. 16). The objective of wood drying is to bring the moisture content close to the expected value that a finished product will have in service (Chap. 13).

Equilibrium Moisture ContentEquilibrium moisture content (EMC) is defined as that mois-ture content at which the wood is neither gaining nor losing moisture. The relationship between EMC, relative humidity, and temperature is shown in Figure 4–1 and Table 4–2. For most practical purposes, the values in Table 4–2 may be ap-plied to wood of any species. These values have been calcu-lated from the following equation:

(4–5)



K = 0.805 + 0.000736T - 0.00000273T2

K1 = 6.27 - 0.00938T - 0.000303T2 K2 = 1.91 + 0.0407T - 0.000293T2

For temperature T in °F, W = 330 + 0.452T + 0.00415T 2 K = 0.791 + 0.000463T - 0.000000844T2

K1 = 6.34 + 0.000775T - 0.0000935T2

K2 = 1.09 + 0.0284T - 0.0000904T2

Simpson (1973) showed that this equation provides a good fit to EMC–RH–temperature data.

Sorption HysteresisThe relationship between EMC and relative humidity at constant temperature is referred to as a sorption isotherm. The history of a wood specimen also affects its EMC; this is called sorption hysteresis and is shown in Figure 4–2. A desorption isotherm is measured by bringing wood that was initially wet to equilibrium with successively lower values of relative humidity. A resorption, or adsorption, isotherm is measured in the opposite direction (from the dry state to successively higher RH values). As wood is dried from the initial green condition below the fiber saturation point (initial desorption), the EMC is greater than in subsequent desorption isotherms (Spalt 1958). Furthermore, the EMC

10 20 30 40 50 60 70 80 90

10

20

30

40

50

60

70

80

90

100


Tem

pera

ture

(ºC

)

2 4 6 8 10 12 14 16 20 24



JulyJanuary

mountains

low lands

year


JulyJanuary

mountains

low lands

year

Socio-Environmental Relations of Non-Discrete Spaces and Architectures: Systemic Approach to Performative WoodSocio-Environmental Relations of Non-Discrete Spaces and Architectures: Systemic Approach to Performative Woodvariation of relative humidity











7.4 Formidling/motesal

7.6 Lager

7.5 Multimedia

7.3 Utstill ingsareal

7.3 Utstillingsareal5.1 MiSF - sjef

7.3 Utstillingsareal


skriver

6.1 Recepsjon7.1 Butik7.2 Garderobe

±0,000

+3,100

+4,200

+6,350+6,200

+7,000

+7,000

-4,360

2.0 Magasin

6.7 Reinholdsrom

2.0 Magasin

6.5 Garderobe 1.2 Lager ureint6.1 Recepsjon7.1 Butik

7.2 Garderobe


±0,000

+1,150

+1,150+1,150

+1,15

+1,15

0 2 5 10

snitter1:200

del snitt1:100

BB’

AA’

axometri

PÅ VEI



Austland

Sørlandet

Vestlandet

Sør Trondelag

Farm House from Lende in TimeJæren, 184591

Farm House, Nes, MundheimKvam, 1600 - 170081

6.04

Summer Quarters, Stor-Elvdal18th century7.02

9.05

Summer Quarters - orig. Winter Q.,Åmot17th century8.02

OPPORTUNITY OF USE PENETRATION OF ENVIRONMENT & SPATIAL DIMENSIONS NUBER OF SIDES DISTRIBUTIONSAMPLES’ LOCATION OF ORIGINREGINAL CLIMATE

1°Ci i/e e54% RHi 16% MCi 3°C i/e 54% RH i/e 18% MC 2°C e 53% RH e 18% MC



3°Ci i/e e53% RHi 17% MCi 4°C 54% RH i/e 17% MC 4°C e 55% RH e 20% MCi/e i/e

2°Ci i/e48% RHi 18% MCi 4°C i/e 49% RH i/e 17% MC 4°C 50% RH e 17% MCee

3°Ci i/e48% RHi 17% MCi 3°C i/e46% RHi/e 23% MC 4°C 48% RH 16% MCe ee

3°Ci i/e48% RHi 17% MCi 3°C i/e48% RH 20% MC 4°C 48% RH 23% MCi/e e e e

2°Ci 49% RHi 22% MCi 3°C 48% RH 17% MC 4°C 48% RH 23% MCe e ei/e i/e i/e

4°Ci 52% RHi 17% MCi 4°C 52% RH 21% MC 4°C 52% RH 21% MCei/ei/e i/e e e


2°Ci i/e36% RHi 19% MCi 4°C i/ei/e 35% RH 16% MC 4°C 42% RH 17% MCi/e e e e

SPATIAL DISTRIBUTION OF TEMPERATURE, RELATIVE HUMIDITY AND WOOD MOISTURE CONTENT IN INTERIOR, SEMI-INTERIOR AND EXTERIOR MEASURED IN NORSK FOLKEMUSEET IN OSLO (READ FROM LEFT TO RIGHT)

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Relating Environmental and Social Conditions of Norwegian Traditional Architectures’ Non-discrete Spaces, “Svalgangs”

The unclimatised spaces between interior and exterior, generating the onion principal of the building, securing to different extends visual, sound and climatic penetration, have its place in almost all traditional architectures, functioning as its energy exchange with the surrounding environment.“Svalgangs”, the semi-interior spaces in Norwegian traditional architecture, that are giving various opportunities of use and serving as public-private and indoor-outdoor interface, developed in high potentials of articulation with different or even gradual degrees of permeability in relation to socio-environmen-tal conditions. The GIGA-map is relating such spaces in context of their original climatic location, opportunities of use or inhabitation, options of penetration of overall environment and spatial dimensions, its distribution enveloping the interior spaces and climatic exchange of the onion principle.The GIGA-map is zooming into various scales and layers, relating data and their development through colour coding gradients, their intensity through dashed lines and weights, themes through curvature degrees and arrows suggesting the process of the performance.

GIGA-mapping Svalgangs Systemic Approach to Architectural Performance and Wood as a Primary Medium to Architectural Performance projectMarie Davidová

The data are collected from Norsk Folkemuseet in Oslo - The Open Air Museum, Maihaugen Open Air Museum in Lillehammer and Golomdalsmuseet Open Air Museum.Special thanks to Terje Planke from Norsk Folkemuseet for the consultancy and measurements enabling and to my supervisors Miloš Florián and Birger Sevaldson for consultancy and inspiration.source of climatic diagrams: http://www.yr.no/source of map of Norway: Central Intelligence Agency: https://www.cia.gov/

1

2

3

1

1

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1 1

2

4

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1

1

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3

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3

1

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varia

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aps

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1 2 3

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tem

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of i

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hum

idity

of i

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moi

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e co

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ood

in in

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tem

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emi-i

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emi-i

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moi

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emi-i

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tem

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idity

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moi

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pace


Austland

Sørlandet

Vestlandet

Sør Trondelag

Farm House from Lende in TimeJæren, 184591

Farm House, Nes, MundheimKvam, 1600 - 170081

6.04

Summer Quarters, Stor-Elvdal18th century7.02

9.05

Summer Quarters - orig. Winter Q.,Åmot17th century8.02

OPPORTUNITY OF USE PENETRATION OF ENVIRONMENT & SPATIAL DIMENSIONS NUBER OF SIDES DISTRIBUTIONSAMPLES’ LOCATION OF ORIGINREGINAL CLIMATE




3°Ci i/e e53% RHi 17% MCi 4°C 54% RH i/e 17% MC 4°C e 55% RH e 20% MCi/e i/e

2°Ci i/e48% RHi 18% MCi 4°C i/e 49% RH i/e 17% MC 4°C 50% RH e 17% MCee

3°Ci i/e48% RHi 17% MCi 3°C i/e46% RHi/e 23% MC 4°C 48% RH 16% MCe ee

3°Ci i/e48% RHi 17% MCi 3°C i/e48% RH 20% MC 4°C 48% RH 23% MCi/e e e e

2°Ci 49% RHi 22% MCi 3°C 48% RH 17% MC 4°C 48% RH 23% MCe e ei/e i/e i/e



2°Ci i/e36% RHi 19% MCi 4°C i/ei/e 35% RH 16% MC 4°C 42% RH 17% MCi/e e e e

SPATIAL DISTRIBUTION OF TEMPERATURE, RELATIVE HUMIDITY AND WOOD MOISTURE CONTENT IN INTERIOR, SEMI-INTERIOR AND EXTERIOR MEASURED IN NORSK FOLKEMUSEET IN OSLO (READ FROM LEFT TO RIGHT)

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Relating Environmental and Social Conditions of Norwegian Traditional Architectures’ Non-discrete Spaces, “Svalgangs”

The unclimatised spaces between interior and exterior, generating the onion principal of the building, securing to different extends visual, sound and climatic penetration, have its place in almost all traditional architectures, functioning as its energy exchange with the surrounding environment.“Svalgangs”, the semi-interior spaces in Norwegian traditional architecture, that are giving various opportunities of use and serving as public-private and indoor-outdoor interface, developed in high potentials of articulation with different or even gradual degrees of permeability in relation to socio-environmen-tal conditions. The GIGA-map is relating such spaces in context of their original climatic location, opportunities of use or inhabitation, options of penetration of overall environment and spatial dimensions, its distribution enveloping the interior spaces and climatic exchange of the onion principle.The GIGA-map is zooming into various scales and layers, relating data and their development through colour coding gradients, their intensity through dashed lines and weights, themes through curvature degrees and arrows suggesting the process of the performance.

GIGA-mapping Svalgangs Systemic Approach to Architectural Performance and Wood as a Primary Medium to Architectural Performance projectMarie Davidová

The data are collected from Norsk Folkemuseet in Oslo - The Open Air Museum, Maihaugen Open Air Museum in Lillehammer and Golomdalsmuseet Open Air Museum.Special thanks to Terje Planke from Norsk Folkemuseet for the consultancy and measurements enabling and to my supervisors Miloš Florián and Birger Sevaldson for consultancy and inspiration.source of climatic diagrams: http://www.yr.no/source of map of Norway: Central Intelligence Agency: https://www.cia.gov/

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