We have Norrsken P31a Triple Glazed Aluclad windows. 2 of them have oversized sills that have been supplied in 2 pieces with a dreadful joiner. I have to get the sills repainted for other reasons and have thought about having the lengths welded together with a strengthening plate added on the underside.

Could this work? The long lengths needed are 3.6m and 4m.

They’re probably thin aluminium so probably a bit tricky to weld neatly. Epoxy glue maybe as there will be little load on them? Have a support piece or even a new cill made? I had a bunch of cills made in stainless and black powder coated - not crazy expensive.

11 hours ago, Mulberry View said:

We have Norrsken P31a Triple Glazed Aluclad windows. 2 of them have oversized sills that have been supplied in 2 pieces with a dreadful joiner. I have to get the sills repainted for other reasons and have thought about having the lengths welded together with a strengthening plate added on the underside.

Could this work? The long lengths needed are 3.6m and 4m.

Yes it can, but you'll need to mindful of the upstand as water will find a way through the join with contraction/expansion. Window sills are usually 3m length maximum and split if over that size with a joint connector. You can get them longer (6m lengths) and there are companies that offer them with a welded solution and is very good but you'll pay for it.

Edited 8 hours ago8 hr by craig

4m is above normal sheet sizes, but see this - there’s one supplier mentioned for that size:

https://share.google/aimode/R0xjH0tmE6F3HwIAR