LaForce has recently been approved by UL to manufacture a fire rated, closed back frame! We are the only North American manufacturer who is currently approved for this product.
The reason we developed this frame is to deal with those occasions when clients need a back bend which is greater than 1½ inches. The profiles (see drawing below) allow for those occasions where materials are added to the outside of the fire wall, which themselves are not rated. The drawing shows a single rabbet but we can provide both single and double rabbet profiles.
As you can see on the drawing, there are several restrictions on how this profile shall be used. Most significantly is that since the frame is not being attached to the wall near the hinge rabbet, we can only use pivot sets with this profile and installation detail. Second, is that the installation of this frame must be in accordance with this detail, that means that intumescent sealant must be applied to the fire wall and frame section behind both the door rabbet and the opposite rabbet of the frame.
LaForce has the ability to submit additional requests for modifications to all of our current products including this one. Please feel free to contact us if you have any other unusual conditions and we can discuss options, costs and benefits.
Special thanks to Dave Watson, Director of Hollow Metal at LaForce. Dave has been at LaForce for 5 years and has been in hollow metal operations management for 27 years.