nick200 wrote:Thanks for posting.
I may have to do this in our new house so any advice is welcome!
The ground at the bottom of the garden is far from level and is nearly always damp. I chose to use 8 inch by 2 inch timber for the frame as I am not sure of the exact weight of the playhouse. A frame made from this type of timber will be very substantial and should easily take the weight of the playhouse.
I started work on the base on night after work on my own. The footprint of the playhouse is 8 feet square, so I proceeded to cut the timber.
2 Lengths @ 8 foot long
3 Lengths @ 7 foot 8 inches ( these are approximate measurements, I actually deducted 94mm from the 8 foot lengths, which is the thickness of two pieces of the 8” * 2” as they are actually 47mm thick each)
I then nailed these together to make a 8 foot square with one joist running down the centre of the square. I only put one nail in each piece at this point until I was certain it was square, I then used blocks of wood to get the base level, so that the lowest part of the base was about 2 inches away from the soil. I then added more nails to the structure to ensure it was solid. The important thing is keeping it square and level.
The base was then positioned in the correct place and required supporting; to do this I knocked some 5’ 6” long posts that were 5” by 3” using a post knocker. I knocked these in as far as possible, but it’s difficult keeping the posts straight as they stop moving and start to twist if they hit a large stone etc. When knocking in the posts I left a gap of about an inch between the frame and the post, so that I could place packers in the gaps before fixing, this was so that if a post did move considerably it would not move the frame. The posts were cut off flush with the top of the frame using a reciprocating saw.
On the second evening I was fed up cutting the joists using my circular saw, so I only cut one joist that night and fixed it between the existing joist (approximately 2’ centres). On the Saturday I bought a sliding chop saw for £99 and this really made the job easier, my mate also gave me a lift so cutting the last joist and the noggins was easy and quick.
All the joists were fixed at approximately 2 foot centres and so were the noggins, the noggins were nailed straight through from one end and then skew nailed at the other end.
There are three 5 inch by 3 inch posts at the back, two at the front and I knocked a half split post in the centre for good luck.
All timber was tantalised but after fixing it was given a coat of Ducks back to ensure it lasts.
For most of the fixing I used the Dewalt nail gun with 90mm ring shank galvanised nails along with a couple of 100mm long Turbogold XT screws. The noggins were also glued in using external wood glue.
You can see from this second picture how much the ground is out of level.
I hope this explains it well enough
