bbp belgium

European strawbale building methods

1. General information Evaluation of best building practices

Method of construction: Post and Beam ID: PB-01

Representative: Peter Vos, Belgium

Contact: architectengroep barchi bvba, Tikkelsteeg 11 3770 Riemst

Tel +32 12 / 39 50 28, [email protected], www.barchi.be

Personal quotation

....we built with this method already 10 years...

Table of Content

7. Questionnaire

9. Evaluation sheet

2. Visual description of the method-1

1. General information

3. Visual description of the method -2

4. Technical drawings 2D

5. Explanation of the method

6. Calculation sheet

1- General Date: 27/05/2011 Page 1


2. Visual description of the method-1 Evaluation of best building practices

3D – 1





2-Visual 3D Date: 27/05/2011 Page 22-Visual 3D Date: 27/05/2011 Page 2


3. Visual description of the method -2 Evaluation of best building practices

3D – 2





3-Visual 3D_2 Date: 27/05/2011 Page 33-Visual 3D_2 Date: 27/05/2011 Page 3


4. Technical drawings 2D Evaluation of best building practices





4- Visual 2D_2 Date: 27/05/2011 Page 4

!!!!without scale!!!!

4- Visual 2D_2 Date: 27/05/2011 Page 4


5. Explanation of the method Evaluation of best building practices





Concrete foundations Post and beam construction

including roof and floors

5- Explanation of the method Date: 27/05/2011 Page 5

Compressing strawbales

between the vertical posts

Exterior lime plaster by

machine directly on the

strawbales

Interior earth plaster directly on

the strawbales

Preparation of plastering Covering of wooden

parts with reed at the outside and jute mesh

inside

5- Explanation of the method Date: 27/05/2011 Page 5


6. Calculation sheet Evaluation of best building practices





Material amounts per choosen wall area of: m m

Total wall area 21.378 m² Wall length 4.200 Wall height 5.090 m

Total wall volume 7.696 m³ Wall thickness 0.360 m

Strawbales 7.696 m³

Wood 0.931 m³

Laminated timber 0.366 m³

Regular timber 0.564 m³

Metal parts kg/m2

Costs of material and labour Calculated in subject to the conditions of the producing country

Total 184.47 €/m2

Labour

input/

wall area

Material

costs/wall

area

Labour costs/

wall area

Total costs/

wall area

Straw bales, everything

included 0.400 h 11 14 25 €/m2

6- Calculations Date: 27/05/2011 Page 6

included 0.400 h 11 14 25 €/m2

Wood: Posts and beams,

everything included 9.000 h 24 14 38 €/m2

Outside complete: Limeplaster 1.486 h 30 52 82 €/m2

Inside complete: Clayplaster 1.143 h 0 40 40 €/m2

[1] Material costs for metal parts and screws etc. included in Labour costs

[2] Material costs for metal parts and screws etc. included in material costs

11 14 2524 14

3830 52

82

0

40

40

0

50

100

150

200

Material costs/wall

area

Labour costs/ wall

area

Total costs/ wall

area

EU

R/m

²

Costs of material and labour

Inside complete: Clayplaster

Outside complete: Limeplaster

Wood: Posts and beams, everything

included

Straw bales, everything included

6- Calculations Date: 27/05/2011 Page 6


7. Questionnaire Evaluation of best building practices





1

2

3Stuffing the gabs with loose straw

Bales without gaps

Moisture

How do you ensure tightness of the strawbale wall insulation (stuffing

gaps between bales with loose straw for example)?

Fixation of balesHow are your bales secured in the wall?

Vertical and horizontal compression of the bales with post and beams. Hazel

pins to fix the bales

3.1 How do you deal with potential of rain bouncing from the ground

surface and ground humidity?

Bottom of the first row of bales is lifted minimum 15 cm above the ground

3.3 How do you protect straw in your walls against wind driven rain?

3.2 How do you deal with possibility of water intrusion from building’s

interior at each floor level?

Irrelevant

4 Bales

First we build the wooden structure with the roof. Before infilling het

construction with bales, we protect the whole construction from the outside.

The bales are placed from inside

3.5 How do you prevend water leakage at the window sill detail?

What are your criteria of bale quality (shape, density, moisture

content…)? Give the borderline values.

Humidity < 15% / density 90-120 kg/m3 / bales : 450/350/900mm

With 3 layers of trasskalk

3.3 How do you protect straw in your walls against wind driven rain?

3.4 How do you protect your wall during it’s construction from weather?

7- Questionnaire Date: 27/05/2011 Page 7


7. Questionnaire Evaluation of best building practices





5

6

7

What do you do to secure airtightness of the walls? Wall to ceiling,

opening or ground floor. Is there a blowerdoor test?

Fixing all the gaps, blower door test is planed in future Fire resistance

Wall coating

How do you ensure bond of the plaster/render (if included in your wall’s

assembly) with the straw?

5.1 Plaster

How do you ensure that your plaster/render (if included in your wall’s

assembly) doesn’t crack over connection of two different supporting

materials (for example timber-straw connection)?

Bamboonets overlapping at least 200mm over to each side

Boards, others

Airtightness

3 layers of limeplaster with net

7 Fire resistance

How do you protect the walls from fire, while building and after? Do you

refer to official approvals?

Yes

7- Questionnaire Date: 27/05/2011 Page 8

Documents

bbp belgium