Making vent holes in artificial stone base

[RJRB 688]

Can any builder advise on the following.

Our timber built club house sits on an artificial stone base.

There are no ventilation holes in the base which is approx a 10 metre x 5 metre rectangle.

The void under the floorboard is up to around 2 feet at the most.

It's 7 years since the building was erected and we have areas where the floorboards are rotting.The joists look ok.

Questions are.

What size holes and how many would give adequate ventilation.

Would a core drill go through artificial stone.....how long per hole roughly.

Or is there a better way of doing it.

Thanks

[samssong 10]

Can any builder advise on the following.

Our timber built club house sits on an artificial stone base.

There are no ventilation holes in the base which is approx a 10 metre x 5 metre rectangle.

The void under the floorboard is up to around 2 feet at the most.

It's 7 years since the building was erected and we have areas where the floorboards are rotting.The joists look ok.

Questions are.

What size holes and how many would give adequate ventilation.

Would a core drill go through artificial stone.....how long per hole roughly.

Or is there a better way of doing it.

Thanks

Hire as stil saw with a stone cutting blade and cut perhaps 4 or five 10 inch wide by 7inch deep square holes below dpc or floor level ,then insert 9×6 air grates into precut holes and cement them in with a sand and cement mix of say three shovels of sand to one of cement.

You could also knock out the square holes with a hammer and bolster chisel but it could lead to a bigger hole needing patching up.

Edited June 29, 2017 by samssong

[nikki-red 307]

Bickering and off topic posts have been removed.

 

Please do not start it up again.

 

Thank you.

[illuminati 10]

Are you saying you can core through from the atmosphere side into the void? If so this would be a hell of a lot safer than using a Stihl. Just core multiple holes and put vent inserts in. I think they are around 100mm diameter You can hire core drills and bits from any hire shop, they charge you by the wear on the teeth when you take it back.

[butlers 259]

I agree with illuminati, if it was just a couple if hiles a sds drill with a cheap112mm cutter would do it.

I bought such a set up to do some holes through some 8 inch stone and it did it ,albeit slowly.

Brick abd breeze it chomped through.

[RJRB 688]

Is an sds drill a necessity for this or could I use my trusty Bosch?

[illuminati 10]

Hi RJRB

 

You can buy a Mac Allister SDS drill for around £50 from B+Q. for the money they are fine for DIY and you can keep it for later use. I wouldn't normally recommend cheap stuff like this but I bought one of these years ago and it's fine, just don't get a battery one, mains only. Then either hire or buy a cutter, 112mm as butlers said. Your Bosch will be the usual low level hammer action which won't hack it. You will probably burn it out like I did with my late Dad's trusty Bosch!

Just take it steady and frequently dip the tip of the cutter in water to keep it cool and stop it blueing.

When you have used an SDS drill you won't go back to a normal hammer drill!

[samssong 10]

Just load up the 4 lb lump hammer , aim the Tyszac chisel at the chosen spot and cut out a 9 x 6 inch hole and gobbo in an airgrate , that is how it has been done for a thousand years , no electric needed in middle of no where , no hundreds of pounds to spend on fancy equipment ,just elbow grease and Knuckle rash.

Edited July 2, 2017 by samssong