Advice and options for repairing concrete cill

23 Oct 2011
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United Kingdom
Hi all

I have an external concrete window sill that needs repair. As you can see in the photos it's in a bad way, What's the best way to repair this? and the best way to repair the cracks?

I'm having some building works done at the minute and although the builder is doing a great job he doesn't seem very interested in adding this to the list of things to do, his suggestion was to cut it all off and put a new window in which is is rather costly, add in the extra mess in the only liveable downstairs room at the min (where we're cooking) and it sounds like the last option I'd choose

In addition to self repair are there companies out there who refurb/recast cills like this?

Any advice greatly appreciated as it's pretty unsightly


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your builders reply is the most viable.
however you could remove most of that cill and cast a new concrete cill in situ with some basic timber-shuttering skills and product knowledge.
Long term replacing it would be the best bet, that window looks in decent nick so removing & reinstating wouldn't be too massive a job. Bit chilly at the moment though...
Short term you could do a cosmetic job with car body filler (you can get gallon cans of the stuff from yr local motor factors).
Seen one done like that. First one fitted bricks along to make new sill soldier them side by side but window will need to come out.

Second one chippy knocked up boxing. Bars fitted in the existing concrete, and boxing fitted with screws and a bit of silicone. Then concrete pours in to cast new sill. Looked good when done and option you could do.
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Thanks for the advice and opinions

In all honesty my preference is to cut it off, just off putting at this time of year, especially with the other work going on, but at the same time we’ve got the builders here already!!

the builders concern is the window is bigger than the inside, so quoted for a new one, but I’m not 100% sure it is i think it’s just because of the internal tile cull that it looks that way... off to take some measurements!!

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