Need to drill hole in wide stone wall - advice

Ginger83

Is it possible to drill a hole in the gable wall of an old stone house? The wall is two feet wide or more and I'd like to run a cable through it.

10-10-20

Yes, with a long drill-bit it is. Point it downwards so that it drains back outside and seal it with a suitable mastic.

Ginger83

https://www.boards.ie/discussion/comment/119882093#Comment_119882093

What length drill bits would be available? It's a very thick wall.

T-Maxx

Longer than 2 feet in anycase. Have a look at the likes of screwfix.

waterwelly

https://www.boards.ie/discussion/comment/119882516#Comment_119882516

I bought 1 metre bits before, eBay or Amazon I think. If the stones are exposed you might be able to remove one from one side to make things easier.

The centres of these walls tend to be hollow too.

screamer

It’s possible but it’s one b:tch of a job. Go and hire something to do it if you’re doing it yourself, a regular drill will not stand up to the job.

Ginger83

https://www.boards.ie/discussion/comment/119882717#Comment_119882717

Will an sds drill not do it?

Ginger83

https://www.boards.ie/discussion/comment/119882712#Comment_119882712

That length would be excellent

screamer

It might depends on the type of stone you’re drilling. You can try it and see.

Ginger83

https://www.boards.ie/discussion/comment/119882902#Comment_119882902

Screwfix have a 22×1000mm bit. Sounds like the job and good reviews

T-Maxx

SDS 100%

Furze99

I've done this a few times on granite walls. Use a long thin SDS bit. If at all possible hack off the plaster either side to expose the stonework. The trick is to pick a thicker mortar filled joint on one side and go through that, with a bit of luck you may also hit on a joint on the far side. Most stone walls here anyway have two rows of stone with rubble infill and sand between. One you're through, you can enlarge from both sides using a wider shorter SDS bit if needed.

The Continental Op

As mentioned this can be a bitch. The distance isn't the problem even the cheap 1000mm SDS bits they regularly have in Lidl and Aldi in a suitable drill will do the job. The problem is the crap in the middle of the wall. Because the center of the wall is often a mix of mud/clay and rubble it gets very dry and can move.

What happens is you drill a hole pull the drill out and then the rubble settles in the wall and you no longer have a hole all the way through.

What I have done is drill through with a 24 or 25mm 1000mm long SDS drill then leave the drill in the wall and remove it from the drill. From the inside I then use a length of 3/4 inch straight qualpex and use it to push the drill back out from the other side (or push it through). That leaves a nice clean hole for pushing a cable through. Its not as always as easy as that and might take a few attempts after redrilling the hole. The problem with no pipe lining is the hole might pass through void spaces making pushing a cable through difficult but obviously you can push a straight rod through first and pull the cable through.

Ginger83

https://www.boards.ie/discussion/comment/119882994#Comment_119882994

That's a good idea about the qualpex as it would be like ducting

The Continental Op

https://www.boards.ie/discussion/comment/119883375#Comment_119883375

If you have a bad wall then it can still be a pig to get in but is better than the option of a hole that fills in again and again and again. The OP might have better luck as he is drilling fairly high up on the gable end. The fill will probably be very dry but there won't be as much weight above it to force the hole closed.

10-10-20

If screwfix doesn't suit then go to any local builder's merchant, they should have long drill-bits at reasonable prices.