by bluebirdnick » 22 Sep 2018, 01:41
Some points of detail/lessons for next time, recorded more for my own benefit really:
1. I forgot the straps. Will add them over the weekend, weather permitting. I'll have to fix them to the concrete floor or blockwork.
2. In the thread above, I asked whether I can use aerated blocks on the exernal skin. I did do this on the wall which is tight to the the fence, with 140mm wide blocks. I gave Celcon/H+H a call beforehand to check with them what I am doing, which will include dropping the box profile cladding on that side to ground level so as to cover the blocks. (This was something I had decided to do to allow me to use longer metal cladding sheets, which give me flexibility on design of the building when I move it). They said it was fine, so that is what i have done. To try to err on the side of caution I did "render" the external face with a coat of 4:1 sand:cement mortar. Time will tell if it will work.
3. On the opposite wall I used bricks as the external face, and used full 100mm blocks (rather than 100mm cut-in-half blocks) on the internal face as we were struggling for time to get them cut and I had enough to lay that skin in full block widths. It will look a bit odd on the inside and will make strapping a bit harder/less effective, but it meant we got the job done in the time we had allotted to it.
4. There are doors front and back, so the brick wall is actually 2 separate "U" shaped walls. My errors mean that one is about 8-10mm lower than the other, but both are level in themselves. I therefore screwed some 9mm ply onto the bottom of the sole plates on the low side, and painted this with end grain treatment. Not ideal, but it seemed like the best way to deal with the error in the brickwork.
5. You can barely see it, but I did put down some narrow DPC that does sit under the sole plates. Next time I will use wider stuff. In this build I am hoping it will perform 2 tasks: protect the timber against rising damp; and also provide a clean surface for the sole plates to be cut away from in a year or so's time
6. With a view to preserving the wall panels and to facilitate moving the building in a year or so, I used building silicone rather than mortar to bed the wall panels onto the plinth. My theory is that it will be easier and cleaner to slide a blade underneath the wall plates to cut them away from the plinth than it would be to get them out of mortar. And to be honest, I really couldn't face any more sand and cement at that point. I also put dabs of silicone under the dpc - I didn't like the thought of it unbonded to the plinth and so subject to slip around.
7. I cannot bolt the wall panels together! I need bolts at 6 junctions: each of the corners; and the joins in the middle of the two long walls. I've managed about half of this using my dad's drill, but he left this morning and my 18v drills just don't have the power to get through. The only mains powered drill I have now is a 5kg SDS monster, and that is far too big to get into place to drill the holes I need. I've temporarily clamped the unjoined corners. I think I'll find a way through the connections in the middle of the long wall, but the corners have me stumped. When using my dad's drill I had most success with a 12mm auger bit, but my drill dies when trying to it through the corners, even when I do it in phases.