Renovating an old house

[bricky48not]

Hello There, I'm just in the early stages of this project and I'm trying to work out a few estimates of cost for modifying a (very old) terraced house before the builder starts working on it. After I remove all the old plaster -from every internal wall, is there a rule of thumb for applying sand and cement per square yard. The walls are decent and the brick and old cement (lime based probabably)seem in decent shape. I'm no expert, but I know I'll need to 'tank' the ground floor walls which are dampish near the bottom at some places.
The internal walls for all 3 floors (there is an attic) are all around
55 -60sq. metres.
Even if I was thinking of dry-lining the walls with boards, I think all the walls need sand and cement first (mix 3:1 or 4:1??)

 

[freddiemercurystwin]

Don't forget to allow for insulating all the walls if Building control get wind of the works.

 

[bricky48not]

I have got planning permission and had my drawings approved by the local council's Building Regulations dept. The drawings/regulations relate to mainly an extension that is also going to be built on the rear of the property and although they have been strong on the attic ceiling in the old house insisting on a 50mm air gap with 50mm timber battens fixed to existing rafters and 70mm celotex fixed between the new rafter depth and 45mm celotex fixed at 90 deg. to rafters with 12.5 mm pl.bd.....they have not made any reference to the existing house walls. However, although the walls are v. thick, I think they will need insulated.
Will this be achieved with insulation between the sand and cement and the dry lining boards?

 

[joe-90]

Use insulated PB. You'll regret it if you don't.

 

[freddiemercurystwin]

Once you remove more than 25% of the plaster or render back to the masonry BC will be able to insist on you updating the insulation, this usually involves insulated plasterboard as Joe mentioned or insulation between battens and plasterboard.

 

[bricky48not]

Yes, That makes sense....I should have known that the plaster bd' would have the insulation on it.
This adds to my initial question on the estimate of applying sand/cement to all the internal walls. The second question then if any one can provide, an estimate approximately to insulate all the walls with plaster boards for the same area?

Is there a rule of thumb for both of these pices of work for cost estimates per sq.m

 

[mointainwalker]

initial question on the estimate of applying sand/cement to all the internal walls.

Why are you doing this ? Is that going to be the final surface, apart from paint, say ?

 

[bricky48not]

The plasterboard will be skimmed first and yes then painted.

 

[mointainwalker]

But my still-unanswered question is

" why are you applying a sand/cement render if you are then putting on pb " ?

 

[freddiemercurystwin]

I thought that was his 'waterproofing'?

/runs from thread

 

[noseall]

If masonry walls have been subject to damp related problems due to hygroscopic salt saturation etc, then prudence would suggest a decent scratch of sand/cement render (with appropriate admixtures of course), prior to dabbing gypsum products or fitting insulation.

 

[joe-90]

Yeah but that Prudence is a dopey mare.

 

[mointainwalker]

@ noseall

applying sand/cement to all the internal walls.

The house is over three floors.

 

[noseall]

@ noseall

applying sand/cement to all the internal walls.

The house is over three floors.

I didn't say rising damp........

There are a few instances where hygroscopic saturation can occur whatever the height.

Using sand and cement, coupled with say S.B.R. and a waterproof additive is the only way to stifle aggressive contamination and subsequent leaching.

Gypsum based plasters are practically useless and act like a sponge.

 

[bricky48not]

I do appreciate all the comments and I have sought advice from the odd builder friend by removing sections of the old plaster and demonstrating the condition of the internal 'brickwork' -which is decent for an old 1874 property, but the internal walls will require a sand and cement platform to add the insulation/plasterboard to the walls. I am asking the forum a basic question to assist me in starting to try and estimate the cost of all the materials for the renovation because the builder (who is intending to help me with the task) has asked me to have a go myself at what the material costing would be -just to compare my estimate against his estimate taken from my drawings. This is because he is trying to be honest with me ...and because he cannot start the work for a while it is an exercise I hope to carry out with some help from you guys. So is there a 'Rule of thumb' of costing for sand and cementing a wall per unit square metre please.