How close to the old extractor fan hole can I drill a new one?

[barki]

Hi all

Just fitting a new kitchen for the wife. The location of the cooker hood is about 12" from the location of the old hood, meaning that the hole through the external (cavity) wall isn't in the right place any more.

Not wishing to make a mess trying to drill it out with loads of tiny holes and a chisel, I'm going to hire a decent core drill from HSS.

I'm just a bit concerned about making another large hole in the structural wall of the house, so close to the other one?

Is there any rule of thumb about doing this? Perhaps I can fill the old one with something substantial to retain its structural integrity?

Cheers in advance

Tom

 

[tomfe]

Will be fine, 300mm is quite far from the hole and even if it was right next to it it would not have structural effect.

Depending on your brick core drilling can be a pain, start off with the core drill and make a nice round hole then stitch drill out the middle then use the core bit to make it nice.

 

[Ian H]

Ask them how much they add onto the hire for wear to the core bit.

It might be cheaper to buy the Mexco kit from tool station/screwfix depending on the size of your hole. I think the kit is £70 and goes upto 110mm

 

[^woody^]

Holes are nothing structurally. You could drill it next to it if you wanted to.

If you core the new hole out, and the existing hole is round, you can normally put the core peice into the old hole and point it up.