Footings and internal walls

[Marym2]

Hi

Will be doing a bit of work and need a bit more info then I already have, so  here goes

The Footings will have to be done in stage' as I will be leaving the oringal stone and mud in, the floor is earth and I hope to dig at least 1 metreX6oo so as the external wall is 12+ metres long what would be safe in terms of lenght and what sort of stage'?

The floor will be concrete but want to have underfloor heating,    am I correct in :

DPC /      200 concrete then Pipework layed in screed of 50 ?

Walls     Only need Blockwork up to 2.75 (beams are supporting iron sheet roof)  which I hope to replace with slate.What would be the best insulating material, been using kingspan here (England) whats the same 'ish'

Thanks in advance hope thats not too unclear.

[Chippiepat]

If Iv'e read your post correctly,? your building a new internal wall 12m long inside the existing stone wall, if this is the case & the new block wall is non load bearing a footing is not necessary, I would simply build the wall off of the new concrete base with maybe one or two piers to break the run.If the new slab is to be laid on compacted hardcore or sub base then 100mm concrete with mesh reinforcing should be adequate( possibly thicken the slab to 150mm at the edge under the wall) Can't help you about the insulation, I am not a qualified engineer but have been involved in the building game some 30yrs, I'm sure if my reccomendations are incorrect someone will soon be along to put them right.

Good luck,

Pat

[Marym2]

Yes. Thats what I am doing I forgot to mention that the wall will not be load bearing overall (unless the other old one falls down) but I hope to put in some Double Glazing windows  and doors which I will need to remove some of the orginal load bearing then have a steel/concrete lintal above them which will then support the roof. I also have two sides which will also be blockwork. The reason for doing this first is just in case I have a problem with the Permis and cannot have doors windows (farmer says tell no one  but as read on this site 'at your peril') I already have two small windows but this is not enough light and we have no access to our garden. Slab sounds right but wanted to know just in case!

Thanks chippiepat

Mr Decorator

[Dave&Olive]

hi

  ok sorry thought about it and don`t like it  because...

 first off before you seal up the stone work you need to rough point it up first ( take it you are going to build a cavity wall with block work ) and you need to vent it

second where is the insulation going in the floor ,or are you going to heat up the moles ?

third even 2.75 mtr high wall in block is a lot of weight for just  a 4" floor ( you say 8" not needed )

in the uk all ground floor walls have footings even none  supporting walls unless they are studwork  type walls

also you need to insulate the floor from the blockwork  because you are going to use under floor heating ...why heat the  vented cavity

do it right do it once

 dave

 

[BIG MAC]

I would excavate footings about a metre deep in bays no more than 1500 wide along the wall make sure the wall is in good nick and pointed as neccessary drill a few air holes maybe then stand egg box type vertical DPM similar to Delta membrane over here but thinner profile cast footings so that you have created a way for water to pass up and down the outer wall without affecting the inneryou can then excavate inside the ring beam to formation level for hardcore, blinding  and DPM  which can then lap up the vertical DPM. Install fibreglass batts Build block work then Cast RC slab  black jacking it (going up the new blockwork about 500 mm) Install insulation and heating then screed.

You need to work out the levels but this way the outer walls should not dry out and fall apart yet the interior will be insulated and dry.

[Chippiepat]

If the block wall you are building is just to give you a flat finish internally and is non load bearing still cant see the need for a footing, sorry to disagree Dave but I have built many a non load bearing wall off of the slab in england all under the supervision of the architect & local building inspector, & we are in an area that suffers from clay movement.Agree totally about the floor insulation & venting the existing wall.Can't really see what the idea of the wall is? Big Mac,To the best of my knowledge the depth of footing is determined by the suitability of the ground that it bears on & just to say go 1M deep means nothing, & I certnainly would'nt disturb that much ground around my existing walls if I didn't have too, if done in bays these have to be tied together properly or you just end up with many 1500 individual footings not acting as one. 

[Dave&Olive]

[quote user="Chippiepat"]If the block wall you are building is just to give you a flat finish internally and is non load bearing still cant see the need for a footing, sorry to disagree Dave but I have built many a non load bearing wall off of the slab in england all under the supervision of the architect & local building inspector, & we are in an area that suffers from clay movement.Agree totally about the floor insulation & venting the existing wall.Can't really see what the idea of the wall is? Big Mac,To the best of my knowledge the depth of footing is determined by the suitability of the ground that it bears on & just to say go 1M deep means nothing, & I certnainly would'nt disturb that much ground around my existing walls if I didn't have too, if done in bays these have to be tied together properly or you just end up with many 1500 individual footings not acting as one. [/quote]

 

the question states under floor heating , you want to build on top of insulation

sorry

dave

[Chippiepat]

slab, insulation, heating pipes, screed.

Finish.

[Dave&Olive]

[quote user="Chippiepat"]

slab, insulation, heating pipes, screed.

Finish.

[/quote]

 hi ok

          this means he is still going to build his blockwork walls of a floating floor

         Dave

 ps Chippiepat this is not an argument just want to help him get it right

[Marym2]

Thanks, yes not an argument, theres enough on other parts of this forum, just an opinon. I'll try and clarify. I have an old grange, the floor is terre, the walls are stone (metre inside 1200 outside) then it is mud, there are 2 small windows and the height is about 2-3 metres high. there are 3 walls the forth the main one being the exit/entrance to our main house. Overall lenght is about 24 metres. I would like to use the area and have asked various people how I could do this..

I come to the conculsion that if I did the walls in blockwork internally that would give more support to the main bearing beams if I changed the roof to a slate one. I would also like to change my staircase to this area as well, having a dormer at the top so as to make the above area a bit more bright. There is a floor above but the space is at an angle which is not really useable ( although designers may differ) I have been working on a house in London and as of a result of swoping work I have now a conserverty. This has 2 sliding doors 2 fixed Double glazing units( doors are Double as well) and a side door and small fixed unit.each of these are about a metre wide. To my mind this would look great as we not only have no access to our garden at the back but the light is so bad that it needs opening up. So that the back wall, where the windows are, would be opened up and the units installed.

Thanks for your thoughts, I do have some skills in rebuilding covering 30+ years from starting concrete footings to finish but most of this was done a while ago, when the decorating game was in decline and I took on any job to pay the morgage. So its getting it right and not having things fall down on me (or anybody else come to think of it, unless its the Bast888ds who nicked all our stuff, concrete lintels would do fine) I also thought that doing it in stages and caging the steels and dogtoothing the base might give me a stable approach as when I did underpinning I do remember doing this sometimes.

As the Delta membrane was mentioned. I might take a trip to their place in North weald as its near a pub that I use to use. Cannot get to bogged down in rebuilding, have to have a life as well.

Okay so anymore thoughts are welcome.