Building Insulation

This was a job I was not looking forward to. Cutting the 100mm blocks of celotex dense foam insulation is laborious. The dust from the sawing gets up your nose, so the face masks helped with this, and in your eyes. It was impossible to wear goggles as they steamed up. So I had to get used to itchy eyes and just crack on with the work ready for the electrician to begin sometime on the 25th of November.

The internal roof was first. The initial layer was 100mm of dense foam celotex and then the rest of the fill, 125mm, was earth wool flexible bats.


The foam insulation had to be measured and cut carefully so it was a snug fit between the roof timbers.

Once this was all in I then began the itchy work of putting in the earthwool. Once the foam insulation was in the ceiling I began on putting the 100mm of earthwool into the walls. The external walls already had a 100mm of dense foam insulation on the outside.


Interior Insulation

This week I had ordered the interior insulation and also went to pick up the external Larch cladding from Cromartie Timber near Strathpeffer.


Nick who runs the sawmill was really helpful. He turned my order around in less than a week. All of the timber is sourced locally from Ullapool and nearer to Strathpeffer. The wood yard reminded me of sawmills that were dotted about all over the UK when I was a very young child in the 60's. They seemed to disappear as I got older and wood was something that you bought from the big chains.

While there Nick showed me the Larch flooring that they produce so I pre ordered some for the studio. It looked and smelt really good.


I went back to pick the larch cladding up around 5pm as the light was going. People were still working and the large saw outside was busy cuting up a large piece of timber into planks.

Towards the end of this week the interior insulation arrived from Caley Timber, so I need to crack on and get this installed and covered by the airtight membrane ready for the electrician to come and complete the first fix. Simon will be dropping back to help with internal panelling and the stud walls for the bathroom, kitchen.


Internal Flooring


Once the membrane was on the roof we decided, while waiting the three weeks for the windows, to further protect the whole roof with a tarpaulin so the inside wasn't damaged by water getting in.


Once this was in place we started on the internal floor. Sealing the gaps between the joists. We installed a thin batten of wood around all sides of the joist openings at the bottom then used the left over 10mm ply, that would have been placed on the roof, cut and placed in each joist gap on top of the battens. We screwed each ply piece to the battens then sealed each ply piece with silicone to prevent wind and animal ingress.


Once this was done the foam insulation, 100mm, was cut and placed in each of the joist cavities. We then completed the insulation with 100mm of rock wool. On top of this we placed an airtight membrane and then sealed this with tape. Then we cut the ply to become the subfloor on top of which the final flooring would be fitted. As you can see above we also made sure the pop ups for water, drainage electricity and network came up through the floor in the correct places. The pipes going out through the floor were then neatly connected to the soakaway drainage pipe.

We again thought about the thickness of the ply sub floor. In the specs this was set out as 18mm. Simon suggested that we use slightly better quality ply as well as choosing something thicker at 22mm. Again this served to create a very flat and rigid floor.


In Skye, even more than on other builds the attention to detail to prevent wind infiltration to the inside makes a massive difference to the feel of the building once complete. All people who come to the Blackhouse and Hen House are amazed at their warmth and ease of keeping warm with very little energy. The lack of unplanned for draughts is also commented on frequently.