Awkward Gap

23 Jul 2003
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United Kingdom
I have two quite large holes in an outside wall, where the previous owner had installed the toilet wastage pipe, they had not properly filled the holes where the wastage pipe is attached to the wall.

These gaps have been there for 10 years so structuraly its not a problem, however for insulation and asthetics I would like to fill these holes. The gaps for getting to the holes however are very small, (imagine, the pipe covers the front of the hole), you can probably get your hand in but you couldnt get a brick through.

The biggest of the two holes are about 12inches in width at the widest point about 6inches high and about 8inches in depth. I was thinking off filling these holes with expanding foam filler but I'm not sure whether foam filler will expand enough and I dont want to end up buying loads of cans. The best solution is obvously bricks and morter but that really isnt an option here.

Can anyone recommend some other method or product, or endorse that the foam filler will probably do.

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If you can get to both sides I would fill the outside with a few inches in depth of exterior polyfilla or similar (make sure its for exterior use). When the filler is drying stipple with a sponge to get the 'brick' effect.

Then from inside fill with the foam, when the foam sets cut back a few inches and use filler again to seal the foam off and repaint.

The outside filler can be painted with something like Sandtex in a similar colour to your existing brickwork.


i put an extratarctor fan in and used expanding foam for the gaps, let it set, trimmed it back flush, painted it with sandtex, works a treat, just like eric_cartman said
If your hole is behind a pipe, can you not remove a couple of bricks from one side so you can gain easy access, then replace bricks behind the pipe first. A 12in by 6in hole is quite large to fill with foam and will not look as good as brickwork.
:rolleyes: :rolleyes: :rolleyes:
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Buy a large can of Foam and empty it into the holes. Believe me it will fill them no problem. I once had a full can drop on the floor and bust the valve causing it to leak uncontrollably so I dropped it into an empty dustbin. An hour later the bin was half full with a solid mass of Foam. One of the lads on site ended up carving it into a little armchair for his lad .It looked great all smoothed off and painted.
What a cracking idea for furniture, I need some new chairs :cool: .... seriously it seems as though the majority vote goes to the foam filler.

Thanks all

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