Halfway through our building process there are little details waiting to be solved daily. I take a breath of relief realising that with every decision there is one less to be made and that the main building components are already in place. They are the very skeleton and muscles of the house. Here are the details of what we finally went with.
I have already described our main ideology about healthy construction materials. At that time we didn't have a complete break down yet. Now, in the middle of constructing the house I think it's the right opportunity to share with you our exact choices of wall compositions, roof and windows.
The vertical exterior walls are built around a solid wooden frame represented by thick studs and insulated with a combination of a blown cellulose and wood fibre boards. On the outside the walls will be cladded with vertical 15cm wide spruce boards to enhance the simple barn concept of the house even more. On the inside we will also be using wooden cladding.
Exterior wooden cladding samples. We prefer the middle one, although the choice is not final yet. Originally we wanted a very dark colour. Things change and evolve as we progress further.
Two load bearing interior walls are 18 cm thick wooden sandwich panels featuring probably a hemp sound insulation. The main living room wall is due to be made of non-fired clay bricks and the wet areas will be sand-lime bricks, which are very sturdy and provide wonderful sound insulating and heat accumulation properties. Most of these will be finished with a layer of natural clay plastering.
Clay is not only pleasant to touch and look at, but as a natural material it features remarkable moisture control, heat accumulation and sound dampening properties, too.
An update: after consultation with a natural building materials specialist we decided to replace the two sand-lime brick walls bordering with bedrooms with non-fired clay brick walls instead. They should be yellow colour on the picture below.
The bottom of our house has got a fairly unusual composition as it is raised off the ground. It sits on a concrete pier block foundation. Thanks to that we are able to insulate it to a very high standard and prevent challenging thermal bridges.
Our roof has got a 33 degree angle. My husband specifically persisted on this requirement. I was considering to cover it with terracotta roof tiles, but after we changed the house design and decided to make it more barn-like, we finally went for straight standing seam panels made of metal.
We are using certified triple glazed wooden windows of A category energy efficiency. The frames are dipped in an ecological varnish with a 10 year maintenance free warranty. The glazing of the south facing windows will have a better solar factor for improved solar heat gain in winter. The windows come with cabling for an alarm system as standard.
- Uw=0.79 W/m2.K - heat transfer coefficient of the whole window
- Ug=0.5 W/m2.K - heat transfer coefficient of the glazing only
- g=0.5 - solar factor
- +10.9 W/m2.K - overall energy efficiency meaning the difference between the heat gains and heat losses
The front door is also made of wood, protected with a double layer of a UV, wind and scratch resistant varnishing. It also features the highest safety triple lock mechanism.