Hole in my house - how to fix?

[MILdesperandum]

Hi, we removed a waste pipe from a sink and now have a 2inch hole to fill up in our exterior wall. It's on the most exposed wall of the house so keen to get in filled before winter in but what to use? Mortar? Expanding foam?

thanks!

[PigletJohn]

mortar on the outside.

You can use expanding foam on the inside, then trim back the blob and use filler before redecorating. Or mortar again, as you will probably mix up enough.

If it is a solid wall (no cavity) you can fill the entire hole solid with mortar. It will be easier if, while you are working, you block the hole in the side you are not filling from, then you can poke it in solid with a broom handle. Otherwise it will slump and sag.

If it is a cavity wall, you must not let mortar fall into the cavity, so you have to block it before pushing in mortar. A handful of loft insulation, pushed in tight, will do.

[MILdesperandum]

Thanks Piglet, it is a cavity wall. Will get googling how to mix mortar clueless

[PigletJohn]

for such a small job, buy a small bag from a DIY shed (like a bag of flour) of readimix, if you can find it in a small enough bag. You will not be able to carry a 25kg bag Mix it in a ice-cream or tupperware tub. Add less water than you think, mix well, it should be like a stiff cake mix that does not slump like mud.

If you pass a (very small) building site, ask if they can spare you half a bucket, and try to give the builder a fiver. Use it within an hour.

If you still have the piece of pipe, stuff the end with newspaper and poke it part through from the inside to prevent mortar falling into the cavity while you fill from the inside. The mix will go stiffer a few minutes after you poke it in, as the brickwork absorbs water from it. Protect from rain for 12 hours as it will wash away until set.

[MILdesperandum]

lovely - will look out for builders on my school run later

[PigletJohn]

take your own bucket and wear wellies.