rainwater Leak on mortar round door lintel (ed.)

3 Jul 2019
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United Kingdom
Hi all. After 18 months we have just started to get rain water coming in to the house between the top of the bifold door and the plaster. The rain has been heavy and upon investigation there is a small hair line crack which runs the length of the first mortar line of the three rows of bricks which sit on top of a steel lip which has been spot welded to the underside of the steel rsj. This steel lip comes sticks out the width of a brick and allows the three rows of blue bricks to sit on the lip. It seems that the hairline crack on the outside must be letting small amounts of water which in turn is running down the welded steel plate and into the house (the steel plate actually falls back towards the house in terms of level). The welded plate finishes inside around 15mm further inside than the bifold frame which is where the water has gathered and spreads around a meter across one of the bifold panels.

I’m guessing the solution is to chisel out a 1/4 inch line where the hairline mortar crack is and fill it nicely with a flexi mortar sealant of some sort?

Any suggestions for an fairly confident diy’er or should I just pay the £300 excess and get the insurance company in?


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It might be coming in higher up - is there a cavity tray and weep holes? I'm not sure an insurance company will cover poor workmanship. You will invariably get a hairline crack where mortar bed meets steel.
Hi cdbe. I can’t remember anything like a cavity tray being installed. There is a bedroom window above the area though and the bottom corners both need pointing by the looks of it. Could it be coming from there maybe? I doubt it’s coming from higher than that as the bedroom window over hangs the area effected?
This picture might explain better


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What's the wavey metal at the top of the triple blue brick course? Looks like you have another steel in there or something?
There is an angled mound of cement under the lead which slopes down and away from the wall. The lead is sealed into the main brick wall. The seal is tight.

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