Purchased a 1950’s ex-council house in the summer. Currently stripping the house back to the brick (or block) with an aim to modernise, insulate and build an extension (sadly not self building the extension). 
 

We have hit few problems so far apart from a bulging concrete floor sitting on earth which we will need to dig up and renew with a new slab soon. 
 

Still waiting on plans to be approved for the extension, keen to use Durisol blocks for this due to speed. 

Welcome.

 

Take care to be accurate with whatever is underneath.

Hi and welcome

 

A lot of these bulging floor problems were the type of concrete used that swelled, often a lot of fly ash used in them.

 

Take the opportunity to dig much deeper and put plenty of under floor insulation. Often the hardest thing to do in a renovation so being forced to dig it up gives you that opportunity.

Indeed. I had one damp course guy say he would dig it out and put in a timber floor until I took him outside to show him where ground level was and that there was no space for air bricks. He said he would dig a trench in front of the room 13 inch deep for the air bricks. I didnt take him up on the work.

 

Someone else quoted nearly £3k to redo the floor. Im going to do it myself and hopefully save some money in doing so.  

I don't think you will end up saving any money, as you will put the money towards insulation instead!

I’d be paying for insulation on a professional job though anyway as it was costed into the price. Id calculate for the size of the room insulation at around £400 and thats for 100mm Kingspan. Should be marginally less if going for a different brand?

If you are doing it yourself you might consider digging out a bit deeper to get 300mm EPS under the concrete slab