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Type A & B Sliding Door Thresholds?

Jessie Bullard

Registered User
Joined
Aug 14, 2020
Messages
2
Location
Sherman, Texas
Hello All - first post, so please forgive me. Please let me know if there is a more appropriate forum in which to post.

I am working on a multifamily project located in a small town in North Texas, 65 units total, with a third of them being located on the first floor (no elevators). This is one of the first multifamily projects of this scale that our office has worked on. The city follows IBC 2009 curently. Two of those units are designated as ICC A117.1 Type "A" units and the rest of the first floor is Type "B". We have planned vinyl sliding glass patio doors in all but a few of the units. Based on the threshold requirement exceptions, the threshold can be max. 3/4" with a 1:2 bevel, for sliding exterior doors. On the type A units this applies to the interior and exterior, on the Type B units up to a 4" drop is required on the exterior if it is impermeable - in this case it is concerete (maybe someone could clarify how it makes sense for the interior to need to be accessible but the exterior can have a drop of 4"?). The overall height of the threshold is 1-5/8" but we have planned to recess the slab by 3/4" (to give an overall change of about 5/8" with flooring and add a bevel strip). This is a strategy another architect recommended, but your typical residential sliding patio door threshold has gaps and vertical changes of more than 1/4" within the threshold itself, regardless of the overall height or whether it is beveled on either side.

What do you typically see done in multifamily projects of this type? Does the 1/4" vertical change and the bevel requirements only apply to either side of the threshold but not the track itself? It seems as though, especially for Type B and Fair Housing Guidelines, exceptions were made to allow "standard" although somewhat more compliant, components.
If the threshold truly has to be relatively level, are there brands/systems that you typically see used that are still residential in nature and not expensive commercial systems? Do you usually just see swing doors in place of sliding doors to avoid this issue? I frequently see these types of doors used with no knowledge of the Type A/Type B/FHA requirements, but I have only seen them called out for the overall height being too much. We want to avoid any compliance issues that others in the area have run into.

Please see link for a cross section of some of the doors that were bid:
 

Jessie Bullard

Registered User
Joined
Aug 14, 2020
Messages
2
Location
Sherman, Texas
The other option which we considered was to simply go to all swing doors on the first floor, but it seems like this issue of sliding doors must be resolved in other ways pretty frequently.
 

Rick18071

Sawhorse
Joined
Nov 28, 2009
Messages
2,944
Location
Poconos/eastern PA
On the type A units this applies to the interior and exterior, on the Type B units up to a 4" drop is required on the exterior if it is impermeable - in this case it is concerete (maybe someone could clarify how it makes sense for the interior to need to be accessible but the exterior can have a drop of 4"?).

Doesn't make sense to me. But i had to deal with it once too as an inspector where they made the patio two risers down. They ended up building a deck on top of the patio and made it level with the floor to make it compliant. They put in 6' patio doors with one swinging leaf because they did't think they could make the 5 pound max. door opening force per 404.2.8.

The type B patio 4" drop is a maximum. ANSI section 504.2 says a step must be 4" minimum. So the patio ether must be level with the floor or exactly 4" lower.
505.2 requires handrails on this 4" step too.
 

TheCommish

Sawhorse
Joined
Sep 27, 2011
Messages
1,251
Location
Charlton Ma
Marvin makes a low profile sill sliding and hinged door, there were some aftermarket ramps on my google search.

If the unit need to be accessible it needs to be fully accessible, that is if you provide a feature for an able body person, a challenged person has to be able to make use of the same features.
 
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