Speedfit - Aborted holes

[Arthur]

Hi all. I drilled 25mm holes through the joists under the bathroom but I will need arms like a gorilla to pull the 22mm pipe through. I tried sanding the edge of the pipe and vaseline in the holes but still too difficult. The difficulty is caused by the holes not being horizontal. I think I will have to block the holes. The only method I can think of is 25mm (perhaps sanded or turned down to 24mm) dowel glued with Araldite.

Then I will cut slots for the pipework.

Am I doing the right thing or is there another technique I could try?

Arthur

[Clive Summerfield]

Are you trying to pull it through several holes at once, or just one at a time. I've found the former next to impossible, but managed to do a run through 8 consecutive joists by pulling the full length through each hole individually.

Cheers Clive

[Newshound]

Not worth worrying about blocking the holes, probably. Get yourself an angle drill so that you can drill the holes square. There's a Ryobi kit with a standard and an angle drill, plus a pair of 14.4 volt batteries and a big 1 hour charger for about £110 in Screwfix and elsewhere. Probably the best tool I have bought in the last 20 years.

[Colin Wilson]

Bigger holes to take into account the angle of dangle ?

[keng]

or, 32mm bit and if you can't manage horizontal, use some sort of template/marking gauge and drill from both sides = horizontal.

[John Stumbles]

or an angle adaptor for a regular drill and drill out the existing holes more in the direction you want them, and larger: 25mm is too tight for

22mm pipe, 32mm is more like it. Polypropylene pipe (e.g. Hep2O) is also a lot easier to work with in 22mm than PEX (e.g Speedfit) as it's softer and more flexible. You may also find it easier to join under-floor joints with compression rather than push-fit since you can get the pipe into the fitting with practically no pushing force and see that you've got it home before tightening up the joint, whereas with pushfit you can have a devil of a job pushing the pipe into the fitting if it's already tight in the holes through the joists.

[Arthur]

I am not too confident of leaving the holes unblocked as I opened up one of them into a slot and it is now about 1/3 of the joist heght in depth on one side.

Arthur

[Frank Erskine]

Hmm - not too good. However, just glueing a bit of wood into these holes won't dramatically increase the strength of the bit of joist. If you feel that the joist has been severely weakened and is in a crucial location it may be best to bite the bullet and reinforce that bit of joist with a wood or metal splint bolted through the joist.

[keng]

Forget all about ANY type of drill.

See my previous post and get a joiner as well.

Then, concentrate on your schoolwork and when you grow up and have a house of your own, you'll be able to practice d.i.y.

B.T.W. does your dad know you've been messing about with his power tools ?

[John Rumm]

Given that putting a pipe through a hole will do nothing to restore the structural strength lost from making the hole, it would be best to not make hole that you are not happy about leaving unsupported - since this is what they will be, even with a pipe through it.

How close to the end of the joist are you? How long is the joist in total?

Although the building regs give guidelines about how deep holes can be. and where in the joists you ought make them, they are making the assumption the joist is correctly sized for the job in the first place. This is often not the case in bathrooms where they may actually be well over size simply for the reason they need to match all the others in height.

[Ed Sirett]

Assuming you are not enjoying these posts from under your bridge...

Get a length of 4x2 about 30cm long. Drill clearance holes in it as needed and bolt it to the side of the weakened joist (at the top ) with coach bolts or even better studding, penny washers and nuts.

In future.

1) Drill the holes square and about 28mm. 2) use the Grey Hep2o rather than the speedfit stuff - it is much easier to work. 3) to get a good grip on the pipe you can temporarily put a T on the end to give you a handle, but you should not need to do this if you do 1 and

1. Also you would have to keep removing it.

4) You absolutely need the right kit to bore joist holes. A Cheap (£10) gear box will not hack it IME. A mains or quality cordless right angled drill is needed. You might get away with a quality angled gearbox but I have not seen any of these around of late.

If the joists are spaced at 400 (cf 350mm) you might have room to get a small mains drill and a hole saw into the gap to drill straight holes.

HTH

[Lobster]

Using a square drill bit, naturally? ;-)

[Rob Morley]

That's called a hollow chisel mortiser :-)

[Richard]

Forget expensive right angle drilling machines. Cut the shank off a spade bit of suitable diameter such that it just passes through the joist.

Richard

[Arthur]

Sorry for being slow to reply.

The holes are all no nearer than 160mm (about 17") from the wall. However, now that I think about it, the joists from the adjacent room are protruding through the wall some 10-12". The joists in question are 6" x 2".

If I saw the holes into slots and then use 2 screws each side of the notches would that be strong enough? BTW, The pipes will run under 22mm chipboard flooring where only people will impart weight.

Thanks.

Arthur