Sun, 17 May 2026 15:42:04 +0100 https://www.greenbuildingforum.co.uk/newforum/ Lussumo Vanilla 1.0.3 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=18417&Focus=310428#Comment_310428 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=18417&Focus=310428#Comment_310428 Fri, 27 Mar 2026 09:22:41 +0000 tony
In sustainability terms, it seems crazy to build hugely deeper foundations which use an awful lot more concrete and produce additional problems and costs of disposing of the spoil when it may well not have been necessary. I think this approach would be better for the environment too. :-)]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=18417&Focus=310430#Comment_310430 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=18417&Focus=310430#Comment_310430 Fri, 27 Mar 2026 10:40:28 +0000 djh Posted By: tonyShould the foundations on an extension to a house be laid at the same depth as the foundations on the house itself? If not why not?The extension obviously has to be built to comply with current regulations and hopefully in the light of current knowledge. Which may be very different from the regulations and state of knowledge when the original house was built. So that's one reason for differences.

Current knowledge about insulation, damp and radon and tree roots for example may mean that a completely different foundation design is appropriate. Mini-piles instead of traditional strip foundations, or a passive slab instead of oak beams on earth.

So if you're willing to insure every building build as you suggest against all risks, then go ahead ]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=18417&Focus=310431#Comment_310431 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=18417&Focus=310431#Comment_310431 Fri, 27 Mar 2026 14:51:54 +0000 WillInAberdeen

Istm it is because modern occupants and modern lining materials (plasterboard) are less tolerant of flexing and settlement cracks than was historically accepted.


If built to historic standards, our sunroom would have sagged and cracked a little and the window frames would have been a little off square and needed joiner work to make the windows fit and open, and the plaster cracks and paint would need repairs after a few years.

This probably also reflects that concrete costs are cheaper than they were in 1850 and labour costs are greater.]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=18417&Focus=310432#Comment_310432 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=18417&Focus=310432#Comment_310432 Fri, 27 Mar 2026 19:32:10 +0000 fostertom