Hi
I've been researching deck building so that this time I actually follow some instructions / guidance on how to do it properly (last time was very successful, but some of the niceties weren't perfect - e.g visible joist hangars, posts slightly off vertical etc). And this time it will be double the length and width, so a larger project in any event.
Just for some background, the position is this:-
- 4.8m x 4.5m deck
- starting next to the house (a good few inches away), footings will stand in bolt down post holders on paving flags (not going for ledger board option to avoid risk of compromising dpc)
- ground slopes away slightly (down by about 300mm max)
My first question which most decking advice leaflets don't seem to cover is locating the newel posts for the handrails. From pictures there seem to be two options. Firstly locate the posts on the inside of the frame. This seems messy to me as notching the deck boards around the posts (particularly in the corners) could give some really ugly finishes. Second option is to locate the posts on the outside of the frame. Sounds perfectly straight forward, apart from the fact that I can't work out how you'd do this at the corners, as to be on the outside of the corner for both edges means floating in mid- air.....
Next, a simple question - joists. Some advise using hangers, some advise three 125mm screws. Which would you use?
Next, supporting posts. TMHM (?TMH?) previously disuaded me from putting in effectively 16 posts (4 onto the paving, the other 12 concreted into the ground) to support the overall structure, and instead just concrete the posts at the corners and then use some form of padstone on a level base to support the other posts. Two questions arise here:
- would there be a membrane between the foot of the post and the padstone to stop water transfer, or would conversely you recommend no membrane so that the post doesn't stand in a pool of water.
- second question is how many to put in? Would you just put in posts around the side of the frame (four corners, then two on each side) or would you add an additional four underneath the main body of the deck?
Finally, what order would you do things in? I'm conscious that getting the posts in the right place is going to be essential. My thoughts are to build up the "square" frame, and use that to locate the precise location of the posts. Then put in the posts, secure the frame to the posts and then add additional supporting posts. Then the joists and noggins. Next, newel posts and steps up, and finally deck boards.
Advice, as ever, gratefully received. And for those who are experts about this, a guide which is more detailed than most already on the internet would be a great addition to the diy wiki.
Matt