Drilling in tight space - help!

[JoeJoe]

As part of a bathroom project I need to move the toilet to a position that will require the notching of a floor joist. The joist is 9"x2.5", and the notch is going to be 4" (for the waste pipe) - leaving 5" of the joist remaining.

My structural engineer wants me to fix/bolt a 4"-high steel channel to the remainder of the joist, 900mm long in total, to compensate for the notched part. The floor joists are 15" apart, and the bolts required are 12mm each.

What would be the easiest way to drill these holes (4 in total - two on either side of the notch)? Which tool should I use considering that a "standard" drill probably won't fit in the gap between the joists? Also, this is a tenement flat, so the ceiling of the flat below is fixed to the bottom of these joists, and I really can do without damaging it (enough work as it is).

Many thanks in advance.

[Lobster]

The kosher way (albeit expensive for a one-off job) is with a purpose-made drill like one of these:

(or ) You can hire these for a day's use, but that's still quite dear.

Alternatively, you might be able to get away with cutting down an ordinary spade drill bit to make it short enough to be used in an standard drill.

Finally, you could buy a bodger's delight; a right-angled drill adaptor

- get them off a market stall or ebay (eg

or ).

David

[meow2222]

I wood have thought adding wood to each side of the notched joist wood be easier than steel. Ditto adding noggins to load share.

9x2.5 is big, it must be a large span, or else is rather overrated. IOW in most cases a patch of 2.5 x 5 would be fine as is. Quite a few old houses have 3x3 joists - not very good, but shows what will work.

NT

[Kev]

You can also buy short drills. I have have used a short drill in a right angle drill in a very tight space.

Kevin

[Dave Plowman (News)]

You can usually manage it by cutting down a spade drill bit. You might need several different lengths if things are tight.

[Chris Bacon]

Buy an auger bit (£3.5) and a ratchet ring spanner (£6.5), drill the holes using a piece of scrap batten to push on the end of the auger bit if necessary. Dead easy, cheap, accurate, neat.

[JoeJoe]

I tend to agree, but I am dealing with a "difficult" BCO, and can do without the hasstle I already get for him.

The span is 3.6m, and the situation is in fact more complicated that I described it. The two neighbouring joist on either side of the notched one are already supported by noggins...

[Autolycus]

).

I bought a similar one for a "one-off" job, and that's about what it was - unfortunately one hole, rather than one job.

I didn't expect ground spiral bevel gears running on shafts in ball bearings for my fiver, but neither did I expect end thrust from the chuck to be taken entirely by the bevel gears being shoved into mesh, nor the bearings to get so hot after a couple of holes that the casing was softening, nor the handle to break on the very first hole.

The seller refunded without problem, and I managed with a short spade bit and drilled some curved holes.

[Stuart Noble]

).

A flexible drive shaft? Tedious but doable with a sharp bit

[Ian White]

That method worked here when drilling through pairs of overlapping 2in rafters. Even though the bit needed to be 4in long, there was still an inch or so to spare. JoeJoe will probably find the same.

It may also be worth digging out the little old mains drill that you'd nearly forgotten about, which will probably be shorter than a modern drill with a variable clutch and a large keyless chuck.

[Matt]

The minimum bend radius on them is usually much greater than the equivalent dimension between chuck and handle on a compact power drill. For flexibility they are a good idea in straight (ish) lines, for going 'round corners' they are next to useless.

[Chris Bacon]

Depends on the shaft, and the power they're designed to transmit. I just don't fancy a 12mm bit at 30,000 RPM!

[<me9]

I have a very old black and decker model 1 drill I keep going for such purposes, It won't drill very large holes, just up to 1/2 inch It will fit between joists with a short bit.

[The3rd Earl Of Derby]

Benjamin Middlethwaite

[Stuart Noble]

I'm talking about the drill attachment, which easily gets between joists. OK for the odd arkward job, especially if you get someone else to hold the drill

[NikV]

ratchet brace and bit

[Ian White]

Probably both too long *and* too short.

[Chris Bacon]

Ah. You've come across that situation, too!