800mm toughened glass rule

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Hi

looking to replace a lot of windows in my house. I noticed there is a rule on if it’s within 800mm of the floor then you need toughened glass. Annoyingly all bad one of the windows are about 750mm to the bottom of the frame.

I’m fitting them myself and building regs will sign them off. Does there tend to be a bit of leeway in that situation? Or are they likely to refuse them? It’s a fair bit more expensive to have toughened glass. Probably going to add about £500 to the cost.

Does the 800mm reference the external or internal floor?

Thanks
 
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The 800mm is to where the glass begins or where its visible to the eye, not the frame or the window cill.

No leeway it's a regulation

You have to take both inside and outside into consideration when deciding on safety glass, sometimes the ground level outside is lower than your house floor level or vice versa, in this case I believe you only need to fit safety glass in the none compliant side of a DGU but happy to be corrected
 
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Exactly as Crank says, Its from FINISHED floor level to beginning of visible glass , not beginning of frame. Absolutely no leeway at all, in fact it is an offence for a glass sunpplier to supply glass to you knowing it needs to be saftey glass , and if found out , said supplier could face a hefty fine ( I mean thousands! ) and potentially jail time . If a Building Inspector is doing it correctly then all glass below 800mm from the finished floor ( this includes window seats and bath tubs/showers ) , is required to be a safety glass ( usually toughened ). Usually it is easy to saftey glass both sides of the sealed unit , but as Crank says if either internal or external panes are above 800 then the pane that is above 800 doesn't legally have to be safety glass. All door glass Below 1500mm from finishe floor has to be a safety glass , as does all glass within 300mm of a door opening. You also have to take into account ' critical areas ' , so for example , glass on a stairway ( top , bottom or anywheer up the stairs ) where you could trip, bathrooms where there is a potential to slip in a shower or bath and fall into the glass.
Honestly don't skimp for a few hundred where safety is concerened , you may regret it....I've seen the mess normal glass makes on flesh when it breaks!

I have refused to sell glass to customers who say they won't fit safety glass in the correct areas
 
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when doing window surveys, Ive tended to measure to the window board and specify toughened on anything below 800mm

in the trade theres hardly any difference in price -at least there wasnt a few years back, it only added about £25 a square metre to the price for a DG unit
 
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I use the same principle - 800mm to the window board, the glass might start at 840mm but for the sake of 40mm I know the customer is fully protected

I try and do that as the first thing when indoors -sling the tape from floor to W/B

Its the one thing thats so easy to forget to check when doing a survey -I always write either T or NT against the each item on the schedule, that way I know Ive checked

the one problem is when there are 2 windows the same, one below 800mm one above -easy for fitters to do it wrong way around



generally I dont bother with splitting toughened in lower sashes and annealed in upper if the window is below 800mm its all toughened
 
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I used to often come across that situation where 2 windows were the same size one below 800mm and the other not and the fitters fitted the toughened units in the wrong window.....egits!
 
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Thanks for the info. Problem I’ve got is that on the old frames it’s probably bang on 800mm with the frame included. So depends if there was any variation on frame size for the new set. Guess I’ll have to ask the manufacturer. It’s fine from the outside as that’s lower than floor level inside. The 750mm was up to the window board. So some windows might be 790mm.
 
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As both Crank and Notch have mentioned. If on the cusp better to toughen and be on the save side than fall foul of regs and safety. We are the same , toughen anything within 50mm of the 800.
 
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If your fitting new windows theres no accurate way of knowing where the glass starts so as a failsafe measure to the window board, if thats less than 800mm better to be safe and spec toughened, even if its on 800mm the glass won't be much higher so play it safe, I can show you some of my scars if you wan't?
 
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If your fitting new windows theres no accurate way of knowing where the glass starts so as a failsafe measure to the window board, if thats less than 800mm better to be safe and spec toughened, even if its on 800mm the glass won't be much higher so play it safe, I can show you some of my scars if you wan't?
I’m refurbishing a property to sell it on. But sounds like it’s not worth the risk then.

Add £500? That's a lot of windows - have a look here https://www.woodenwindows.com/windowbuilder.html - with this supplier (which I've used a few times) toughened adds about 10% to the window cost. Worth it though.

I’m going the upvc route for them. It was about £60 extra per window and I’ve got 7 to do including a bow window. So about the £420 mark. Maybe a little less as some windows are smaller.
 

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