Yesterday I started demolishing my new workshop.
I'd managed to get a stud in exactly the wrong place at one side of the personnel door, so I decided to cut out the stud a few inches from the bottom. It came out easily enough, but I did notice that as it hung from its top nails it was about 20mm over to the west, compared to its erstwhile bottom end. Alarm bells started to ring. A quick test showed that the front wall is leaning westward a little. I had altered the bracing a bit and I assume it had moved a bit when I did that, because we were quite careful when we erected it all. Anyway it is all secure and it will right itself once I get the box headers in place.
So I cut a new stud and toe-nailed it at the bottom. Up a ladder it was easy to nail it normally through the top plate. I've borrowed another Paslode from a mate at the Community Workshop and it is wonderful. Bang, bang, bang. Right First Time Every Time, you might say
So by sundown I had the stud in the right place, two trimmer studs and a non-load-bearing header above it.
Sorry, I didn't take any pictures, but I've done the same to the garage doorway today and it looks a bit like this:
The roof trusses will sit directly over the studs. But over the doorways there is a span that is not supported. If we mount the trusses only on the top plate the lot will come crashing down. So we have to provide what the Americans call a header and what we might call a lintel. Something that spans the doorway and is strong enough to support the load above it.
IIUIC, the Americans use a rule of thumb which says that the header should be as deep in inches as the span is in feet. So an 8ft garage doorway would have an 8" header above it. That then supports an array of short studs, called cripples, up to the top plate.
Another option, and it's the one I have chosen, is to make a box-section header. OSB is very strong indeed through its width. You see girders made of the stuff. So I started to make a box.
I cut two pieces of OSB to fill the rectangular opening above the doorway. My nice long track was one of the things that was stolen along with my Festool shopvac, so this week I've bought replacements, but I've bought the 2.7m track rather than the 2.4, which was just that bit too short to cut a standard sheet. It's expensive, I know, but actually it is worth every penny.
There are a couple of things to notice in this photo. The first is the track setting gauge that I use. It allows me to get the track perfectly parallel to the edge and by a specific distance. Unfortunately I appear to be blocking it somewhat. The second if the knock-down table I use. This was posted several years ago on this form by Tiddles. It's all cut from a single sheet and works brilliantly. I could do with it being a couple of inches higher, I think, so, as this on has taken something of a battering whilst it has been in store, I think I'll make myself a Mk II version once I'm installed.
So then I cut a 6x2 and a 4x2. I laid them across the garage door opening and marked off and cut them together so they were identical.
I then laid them on a sheet of OSB to mark that. But I was about to trim rather more than I thought I should. Tape measure. Head scratcher. Plonker. I'd cut the timbers between the trimmer studs and I should have cut them over the studs. They were too short. As I appeared to have mislaid my board-stretcher I had to cut another two, but of course, I'd selected the best, straightest, first time round. I'm getting towards the end of my stock and some of the remaining boards are good at doing banana impressions.
So, mistake rectified, I glued and nailed the 6x2 to the bottom edge of one of them.
When I came to fix the 4x2, it was shy of the edge in the middle by quite a bit, so I got a trigger clamp, reversed the head and sprung it back so that it was flush. I'm so glad that these clamps weren't stolen, they are excellent. Back on the market, too, after something of an absence, but unfortunately not at the price they used to be.
I fixed intermediate studs, the equivalent of the cripples, at intervals, so that the trusses will sit over them inside the box and filled the voids with Kingspan. This is the stuff I've been scavenging from the old-folks refurb along the road. It's 60mm thick and I need 45mm for this job, so there is a lot of cutting. I used my bread knife. It's surprisingly hard to cut this stuff, not because it is hard, it isn't, but because it has a very high coefficient of friction. So it took ages:
But when done it looked like this:
And finally, with the other face glued and nailed, I had a finished header strong enough to hold up the world.
I just need Ray to help me get it up, it's too heavy to manipulate on my own. I can just about lift it, but not carry it up a ladder.
And finally, I thought you'd like to see the difference between the wood I'm putting in and the wood I took out:
The one on the left is old-growth stuff. The rings in the new stuff, on the right, are ten times further apart.
So all in all an excellent day, apart from my car failing its MOT and needing nearly £400 work doing to fix it