Raft foundation & extension

scuby

my house is on a raft foundation, and i'm thinking of putting in a foundation now to make a raised patio area, and maybe in a few years put in a conservatory/single floor extension.

I was hoping to do it in such a way, so i could put in the foundation now and then finish it off now, to be like a raised patio area outside my back kitchen door, and if we do go to build a conser/extension, all i would then have to do is build from the floor up, and not have to go and dig up an ordinary patio area, and waste time and money putting that in first time around.

So, should i put a raft foundation in to match the house, as i presume if we ever went to sell the buyers engineer might not like that ?

and if i went with a raft, is it much more expensive ?

anyone other alternatives ideas ? tbh i think i would rather go with a raft for this, but juct want to check opinions...
house is a semi D

thanks

FesterBeatty

You should not decide the foundation type required (unless you are a structural engineer...?)

Rafts are quite tricky to get right as you need to carefully consider rotations - especially if you're installing one raft adjacent to another - get an engineer!

scuby

thanks for reply.

Just to clarify :

-engineer will be coming out to have a look
-posted here to see what the rest of the Boards posters thought, and if they have any alernative idea, suggestions, so i could ask engineer
-Was not going to be deciding on advice of posters alone

galwaytt

scuby wrote: »

my house is on a raft foundation, and i'm thinking of putting in a foundation now to make a raised patio area, and maybe in a few years put in a conservatory/single floor extension....and if i went with a raft, is it much more expensive ?

....nice idea - I did the same myself, in 2000. Had the 'patio' in for several years, and even had a 3 courses of block built on it, to enclose it. Then, just finished it off several years later.

..re: raft/no raft. Don't see where this thing that 'raft's are extra is coming from. The amount of concrete in the beam under the rising walls, and the subfloor area, is nigh-on the same as any other method: and it's easier/faster/neater to do, as well.

sydthebeat

the thing to consider is that any extension IS going to move seperate to teh original building, raft or no raft. Take precautions when building to include wall starter rails and movement joints. Minimise risk of damage in the future

mickdw

Yes and IMO, there is nowhere near enough attention being paid to movement details in extension builds in particular