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567 Groundwork & Foundations questions

Best course of action for rotten joists where there isn't proper ventilation?

I'm thinking of buying an old terraced house where the two front rooms, hallway, and bathroom on the ground floor are on suspended timber floors. But the kitchen (at the back of the house) and a cloak room of sorts are both concrete. The floor over the timber is sagging in several places, and after a peek under the floor, it looks like there's a problem with wet rot.

I suspect this is due to poor ventilation. There's ventilation bricks at the front of the house which are all clogged with dirt and barely above ground level on the outside, under ground level on the inside. At the back of the house there's no ventilation bricks at all, and the ground level is about the same as the flooring.

The two main options people have been telling me is either replace all the flooring with concrete, or rip out the concrete and use suspended timber throughout, and of course adding proper ventilation in the second case. I'm not sure exactly how that would be done considering the ground level issues, but I've heard that adding the concrete throughout would be even bigger trouble.

Which is the the better course of action?

EDIT: In response to KO Carpentry&Joinery : I had heard that laying concrete may not solve the damp - that it might move up into the walls? Don't know how reputable that person was, though.

Thanks for your input.

why does the drain smell

Can you put tarmac on top of tarmac?

The tarmac on my drive has very solidfoundations but when it was being laid there was a torrential downpour of rain and consequebtly it cooled and is uneven. is it possible to put a thin layer over the existing tarmac?

Is there anyone who could advise me what type of person could search for a missing cat under floorboards or who would have the necessary equipment?

I appreciate this isn't your typical question but I am at a loss what to do. My cat has escaped into the cellar and then through a hole so he was under the living room floor boards. I am in a terraced house so he could have possibly gone far. Please advise if you can.

Thanks guys. Really appreciate you taking the trouble to get in touch.
Sadly its been 36 hours and I've heard nothing now. Turns out there are holes leading in to the adjacent properties so he could have gone quite far as I'm in a row of 6.
Have had the fire brigade out and they have taken up some of floorboards but nothing to see under my property.

Final update. I got my cat Eric back safe and sound !!!!!! The only cellar I hadn't checked was the end house and he was in there ! Somehow he had travelled through 5 house's floor spaces and got there. Thanks for your help guys. It was appreciated and yes two visits from the fire brigade and two from the RSPCA. He is one very important cat !

Can i build off a reinforced concrete slab for a double garage

I am about to build a double garage, it requires no planning or regs, as long as i stay within 30sq mtrs and under 2.5 high, I have already checked with my local council
It will be built in the same place as the garage i just removed which was asbestos.
It will be bigger as the original one was single, I was thinking of a slab 4" floor and 8"-10" around the edge to support the blockwork, would this be ok?

Thank you for you help everybody The only reason i would like to make it as easy as i could is because the access is not good.
But i have somebody coming to dip out a put in full foundations next tuesday.
Thanks again

Who pays for rained off day(s)?

Replacement block paved drive - weather has delayed progress and job will take longer than the 7 days quoted to complete. Single man contractor has hinted I will bear full cost of extra day(s). I thought the builder took the weather risk? I don't want to fall out with him but neither do I want taken advantage of. What's the score?

Thanks for all the answers!
Knowing that my first thoughts were correct as confirmed here, I was able to head off any problems and come to a solution that was good for both of us - he did a good job, and sorted out a few other things that were not on the spec, but better sorted while the gear was on site. So he got an extra day and I'm still happy compared with other quotes. Nice one.

How close can you build a house next to someone elses property?

The land next door to me has been sold and they have just dug the ground next to my property for the foundations. The trouble is that my house is right next to the boundary fence so they have dug about a foot away from my property. Cracks have appeared on the inside of my property since they started digging aand im wondering if they have dug too close to me?

Is it possible to lower a concrete sub floor that has been laid 40mm to high in a single storey extension? Will the vibrations of its removal cause problems with the structural integrity?

Is it costly? Area 34 sqm approx.

How to lay concrete foundation base for single storey extension using shutters


Due to site constriants and the angle of the mini-digger my foundation base is more than 600mm wide.

How do I get a uniform 600mm wide concrete base using plywood shutters.

Please help asap as I need shutters in place for Saturday otherwise it will cost me a fortune in additional concrete.

Thanks in advance.

Hi - please read the full question - he is a prof builder from mybuilder - probs with site meant had to get a small digger which only came with 900 and 300 bucket and even 300 bucket was tight. In hindsight should have got some labourers and done manual dig.

Will have to work out how much additional concrete will be needed

Is is feasible to underpin a single storey single brick extension?

The surveyor has recommeneded exposing the foundations and taking any remidial work required. Eg having an extra internal skin, repointing areas which have cracks etc to stop further movement. He has not mentioned underpinning. Would underpinning the extension prevent further subsidence?
Than you

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