To your added picture. There is no need for it. There is already a sloping concrete sill. Mr. HandyAndy - Really
let's a try a different approach ....... how will water, that passes the seals of the OPs window drain outwards ? as you've rightly mentioned, there are no built in external drains
It won't. There are no built in external drains. But you do not need an extra sill to have drainholes working. The top one will not be sealed along the front, the bottom picture will be. Drained, sealed, run-off ONE sill. Mr. HandyAndy - Really
how would you wind and driven rain proof the installation of a window, with bottom drains, fitted onto any form of conc cill - that doesn't have a stub cill fitted ? why do so many professional people design, and professional window fitters, fit a stub cill in addition to a conc/stone cill ? is this another example of the entire building industry being wrong and a ''handyman'' is right ?
another question ....... why did the nice chap (from a FENSA registered company) who came round a month ago to measure up for some new 3G windows at my home, detail the inclusion of a stub cill, knowing full well they will be sat atop a stone cill ? he's only been running his company for 30 years, perhaps he is wrong as well ?
What are you on about? The concrete sill IS a sill. It is not plastic, it is concrete. It is a sill. If it were plastic, it would be plastic. It's concrete. The same shape as a plastic one, but concrete. It acts surprisingly like a SILL. It would be sealed in exactly the same way as a plastic one. There is no difference. It is a sill that acts as a sill, be it upvc, wood, concrete. Adding a second sill serves NO POINT. What is it that makes you(and pros and archies) think that a concrete sill has no purpose, and that you have to add another? Mr. HandyAndy - Really
Extra 30 quid a metre for sill! If a concrete sill has a run off, there is NO NEED to add a upvc one. IT ALREADY HAS A WORKING SILL. Mr. HandyAndy - Really
calm down dear ........ the image you posted, how would the fitter, wind and driven rain proof the bottom of the frame, while still allowing it to drain ?
What do you mean, wind and driven rain proof? In the same way as if the window was put on bricks with a single upvc sill! Yet instead of a single upvc sill, it is a single concrete sill. What is difficult about that? Mr. HandyAndy - Really
you arent getting it ........ try this one why is there a stub cill detailed, rather than your method of sitting the frame directly ontop of the conc/stone cill ? note the internal upwards facing lip on the stub cill
same question, different words top image, how would you stop wind and water getting under the frame ? - while still ensuring it could drain
Ok Gents, sorry if I started something. Any recommendations on what I should do next ?? From memory the window had drain holes inside the frame at the top opener i.e. if the window was open the rain would not collect in the frame as it would drain through the holes down to the bottom. Therefore I think my mistake was to seal the bottom outside edge with mastic to the cill ? and therefore shall I remove the mastic ? For info the window frame is sat on on a 15mm piece of upvc supplied by the window company, as the inside & outside dimensions differ. I dont specifically remember any holes at the bottom of the frame, but wasnt really looking. Your advice would be greatfully received. Thanks,
you didn't start anything if it's just 15mm, chances are it's just a packer piece to fill gaps, so no channels for water management as you've made such a nice job of it, I'd leave it as it is - unless it's in a very exposed location, facing the prevailing wind - as it's a new window the seals will be good so nothing should pass, it remains to be seen if any condensate forms within the channels, and even if an amount does it might find it's way out somewhere, so don't worry, and don't be tempted to drill any holes in it - nice job
That is really bad advice. I'm sorry 'oops' but please do not take Sean's advice here. The whole point of drain holes is to allow water out(it will get in, even if it's just the frost thawing). Sealed units are ALWAYS sat on packers with air gap below, PURPOSELY so that they NEVER sit in water. If you have nowhere (purposeful drain holes) for water to escape, then very soon the channel will fill and the sealed unit may be sat in water. A matter of months will see the sealed unit break down and need replacing. Now imagine you have sealed along the front but left the drain holes clear. The water will be coming out of the holes, and find it's way behind your sealant, ALONG underneath the window frame, along the sill and into the cavity. Best thing to do is remove the sealant(hope that it hasn't found a way to permanently block the holes), remove the fixed sealed unit, locate the inner drain holes, try to see if the outermost drainholes are clear. If not, clear them or drill some more. Mr. HandyAndy - Really
I'll ask the same question, which you keep avoiding ......... again using different words how will you wind and water seal under the window, where it's sat on the stone/conc cill ? and why do window manufacturers, detail the inclusion of a stub cill
Fingers on buzzers please, and no conferring. Your starter for 10. "Why do people use stub cills when there's a perfectly good cill already in place?"