What size does a bedroom slider window on a main floor have to be?

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Posted by: from Calgary
4/9/2014 at 3:21:32 PM


I am currently thinking of replacing the windows in my home as the ones we have are original (1980's) and are loosing us a lot of heat.

I've had a few companies come and quote, however, one of the companies said that I can't install slider windows in the bedrooms as they would be too small for fire code. He wouldn't tell me what size they would need to be for slider windows and instead told me I had to have casement, which is a higher cost.

None of the other companies told me this so I was just wondering if someone could please advise on what size my bedroom windows have to be in order to have slider windows.


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Date/Time4/9/2014 at 9:36:03 PM

The window would have to have a minimum unobstructed clear opening of 3.77 sf. With a double slider this would mean a window of around 30" x 30".

Double sliders with the tilt in option would be the best for this purpose as casements or awning windows limit the opening area because they don't open fully.

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Lauren in Calgary
Date/Time4/9/2014 at 9:59:52 PM

Thanks for that.

Another, probably dumb, question if that's ok? Is there a minimum size for a double slider window?

Our opening is 45" by 37" and all the companies quotes for single sliders, would it be a problem to fit a double slider in that opening?

Thanks again

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Date/Time4/9/2014 at 10:18:06 PM

If you can install a single slider you can install a double slider. The minimum size of double or single slider is 14 x 14.

The reason they are quoting single slider is they are slightly cheaper.

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Date/Time4/9/2014 at 11:01:09 PM


If your bedroom is above ground level and you have 2 exits from the house you do not need a fire escape window in the bedroom.

In Ontario the sizes for fire escape are minimum of 4.1 sq. fo. and the smaller side opening is at least 18".

The slider that is the best is "double slider lift out" since both sides are removable and only the frame is left in the wall.

If you use tilt windows you have to calculate the size from in between the tilted sashes.

If you are replacing a window then the existing window was designed already to fit the room size and you need just to replace it without worrying about the style.

You can also check with your municipality about the requirements in you place.

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Date/Time4/9/2014 at 11:21:25 PM

As I saw you are in ALBERTA I quoted you Alberta regs.

Follow this link to see for yourself

Hope this helps!

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Lauren in Calgary
Date/Time4/10/2014 at 12:06:03 AM

Thanks for the info and the link Nathan, that's a great help.

Harry, thanks for the advice but it seems it is a little different here to Ontario. We don't want to make the windows larger but the code has changed since the house was built in 1980 and if we retro fit a new window into the same opening that doesn't allow for the clearance Nathan mentioned we can no longer class the rooms as legal bedrooms.

Thanks guys.

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Date/Time4/10/2014 at 10:19:50 AM

The best thing you can do is consult the city local code and ask minimum requirement for your need. Also have all online on internet for your better commodity.

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