West Gable Upper

An Eccentric Anomaly: Ed Davies's Blog

Since my last house-progress post I've finished off putting the tarpaulins on the roof, boarded the top of the west gable and ordered the first batch of steel for the roof.

At the end of my last post I had all the tarps to hand installed on the roof. A couple of days later I popped down to Inverness and got two more. They only had 10m x 10m ones available but I found them easy to cut in two quite neatly using a circular saw after unfolding them one dimension.

One 5x10 half went on the south roof in landscape mode at the east end, under the main bedroom, study and living room windows. The other went in portrait at the east end of the north roof covering the original “proof-of-concept” tarp, which had torn, and the exposed bit of roof below it.

That took me to the 1st of March to finish, selecting days with not too much wind. On the 2nd and for the following few days I battened the upper part of the west gable ready to add sarking boards as I'd already done for the other parts of the gables.

There will be a gap below these boards to match up with the nearest rafter for the roof of the porch/greenhouse. There was then a longish pause while I waited for an occasion I felt comfortable leaving the scaffold tower up overnight so I could use my laser to draw a vertical up across the battens. Using a spirit level is OK but with awkward angles like this with scaffold tower in the way I don't feel I'm likely to do it very accurately.

I did that on March 21st. While I was on site in the dark I took a few astrophotos, the least dreadful of which was this one with Orion poking into the field of view on the left, Aldebaran and the Hyades just above-left of centre, the Pleiades to their right and Mars above and between the two. The Moon was just out of frame to the top left hence the flares from the that direction and the fairly light sky colour. Canon EOS 1300D with the kit lens (18-55mm) at 20 mm focal length, f/4.5, ISO 1600, 6 second exposure. Click for a larger image which shows a bit more detail.

The next day it was forecast to get windy in the afternoon so I went up in the morning to mark out where the boards would go and measure their heights but the wind picked up almost immediately I started so I decided to put the scaffold tower away.

It wasn't till April 1st that I was able to do the marking up and measuring.

I've been numbering the boards, with a slightly evolving scheme, starting with 100 in the middle of the bottom of the west gable, 200 for the middle of the bottom of the east gable, 300 for the east-gable top and 400 for the west-gable top then measured the heights of the tops and bottoms of sample boards from a reference line. In the case of this part this was quite awkward as there's no horizontal which goes all the way across. Then I put the numbers in a little Haskell program (west-gable-upper.hs) to do an ordinary least squares fit on them then print out a table of the dimensions of the boards.

After that, the first bit of April was very cold and windy with a bit of snow lying for quite a few days. A little bit of “lambing snow” isn't much of a surprise but this was a bit more extreme. Here's my estimated daily average heating requirement from the start of November to the end of April:

I had some sarking board to hand but needed more for this gable so on the 7th I went and ordered that and also some “corrugated iron” galvanised and painted steel sheets for the first part of the north roof. The sarking boards were delivered on the 13th, if the steel sheets aren't in by the middle of this week I'll have to chase them up to see what the situation is.

In the second half of April I cut, painted and fitted the boards. The first few were fairly quick being cut from boards I already had to hand, painted last year, so just needing cutting and the ends painting.

The black DPC across the bottom will lap into the edge of the porch/greenhouse roof.

Sarking boards are delivered quite damp, it's noticeable how much heavier they are, so I had to wait a few days for at least the surface layers of the new ones to dry out before I could paint them. Still, I got them done by the end of the month.

The upper and lower bits are slightly different colours. It doesn't matter; the lower bit will be white eventually once it's inside the porch/greenhouse and the top bit will be black. This brown fence paint is just to act as a sort of primer, to cover the back of the boards and to give initial protection for a while.

Since putting those up I've painted a few more boards which will go under the eves, forming sort-of soffits, to close up the gaps between the sarking under the floor and the lower edges of the roofs but I don't want to do that until the roof is properly watertight as those gaps give useful ventilation to help keep the lower corners from accumulating too much water.