Foundations and groundworks to floor slab for extension. What should it cost?

newbie23

Hi all, after much needed advise here on boards, I have my engineer's drawings for the foundations and drainage to create floor slab for a 22.5sq m extension to the rear of mid-terraced property. I only have two lengths of foundation as the build incorporates a party wall on our property built by neighbours.

I have started to price this work which includes the following:
*Excavation for 2 x strip foundations totaling a maximum of 10m in length (formation at same level as existing foundation, I do not know this depth as yet, 1945 built property)
* 900 x 300mm strip foundations with A393 mesh dowelled to existing foundations and also at party wall
* Encase shared drain line in concrete where open for foundation and any other areas of exposure and bridge pipe for brickwork
* Build up block work to floor height of existing property
* Re route drainage to outside new extension, saddling onto shared drain line under property creating an inspection chamber and rodding point outside new extension
* Topsoil removed and filled with hardcore, the new slab will be elevated approx 600mm (we have steps down into garden from house) so I understand alot of backfill required
*Compacted hardcore, dpm, radon barrier, insulation, mesh and 150mm concrete

I have got some prices and they just seem astronomical. Anyone any ideas? Any recommendations for groundwork contractors please PM, south Dublin area

muffler

newbie23 wrote: »

Any recommendations for groundwork contractors please PM, south Dublin area

For this you should post in this thread in the same format as the other posts. Cheers

newbie23

Sorry about that Muffler. Done

muffler

newbie23 wrote: »

Sorry about that Muffler. Done

No probs

oinkely

I'd be interested in a ballpark onthe cost of this too if anyone wants to throw some figures at it?

just curious i guess.

newbie23

Hi all, I'm posting a reply to my own post after having the works completed as I would have found this information useful at the time of pricing. Hope this info is ok with the mods

Got this work done in the end for €4200 + vat. Our contractor was very good and slogged away for the best part of four days overall and I'm very pleased with the job.

The rain came overnight after concrete poured and lasted a few days and ruined the surface of the concrete slab and no time for power floating means that I'll have to out down a screed if I require a smooth finish. Depends on the floor coverings .

Toffypop

newbie23 wrote: »

Hi all, I'm posting a reply to my own post after having the works completed as I would have found this information useful at the time of pricing. Hope this info is ok with the mods

Got this work done in the end for €4200 + vat. Our contractor was very good and slogged away for the best part of four days overall and I'm very pleased with the job.

The rain came overnight after concrete poured and lasted a few days and ruined the surface of the concrete slab and no time for power floating means that I'll have to out down a screed if I require a smooth finish. Depends on the floor coverings .

Hi newbie23,

We're looking at doing a similar extension to yourself. We're in Dublin, if you'd recommend your contractor could you PM me his details please?

Thanks

just do it

Hi Newbie

How much insulation did you put in? Did you use a course of quinlite blocks?

oinkely

Hi Newbie,

sent you a PM regarding the contracter used. Hope you can reply.

cheers

oink