I would first like to give a special thanks to the staff at Firefighters CloseCalls for sending this information to me. So I could share it with you all on Green Maltese.
Also a special thanks goes out to Lt Steve Dykema City of Wyoming Mi. Fire Department for being very heads up training officer and bringing this issue to light.
Attached is info on a new type of stair construction for residential buildings, and a safety bulletin that was put out for the City of Wyoming Fire Department. The stairs are constructed using 2x4s for the main support. The triangles shown hold the stair riser and tread in place. The metal on the bottom of the tread and riser is essentially a gusset plate, similar to truss gusset plates.The inventor of the products has passing on the info below. According to him, if the stairs are on the main floor to second floor configuration, the bottom needs to have drywall. If it is coming from the basement in an unfinished area, no drywall or other protection in required. The entire stair assembly is manufactured in a factory and shipped to the jobsite.
I-Stair FAQ Information from the Inventor:
1.Why is pre-built i-stair better?
Steel stringer brackets. (no 2×12 shrink and split)
Treads and risers are glued and screwed to steel stringer brackets (no squeak)
Installation is simple and fast. (no layout or cutting stringers, treads and risers) Saves frame and finish labor.
Safer: Potential and clients are safe and not nervous climbing temp treads.
Code compliant immediately at installation. (less liability exposure during construction)
2.How is i-stair ordered?
Framers call with wall and floor height, width and landings along with job location.or stair specs are taken from the plans.
3.When is i-stair delivered?
Usually next day, sometimes 2 days.
4.Is there special framing needed?
Hanger board is not needed. Cut subfloor nosing 1-3/4″ and frame the opening consistent for width.
5.How is i-stair installed?
1. Set i-stair and nail top riser tight to floor-joist header & subfloor nosing.
2. Glue stringers to subfloor and bottom riser to floor.
3. Lag-screw stringers to wall studs. ( lag-screws supplied )
If under stair is to be dry-walled, nail 2x4s between stringers every 2 brackets ( 2′ o.c. )
6. How heavy is a typical i-stair?
7.How is i-stair protected on ?
2 pieces of water-shield are provided to slip under the stringer feet,or water-shield is stapled to stringer feet.
8.Why only 2 stringers?
The Tread-Riser-Gusset form I-beams that span the width of the stair.
( Ultimate failure load test, 2040 lbs.)
9.How is drywall under an upper stair supported?
The framers nail 2 x 4s between the stringers every 2 brackets ( 2′ o.c.)(This is not pre-built because of assembly constraints)
10.How is i-stair finished?
The skirt-boards are installed between i-stair and drywall. (The i-stair treads and risers are ready for pad and carpet)
11.What are the two numbers labeled to the riser?
The 1st is the skirt board bottom length.
The second is the skirt board floor cut angle.
12.Can the tread-riser-gusset weather rain and snow?
Yes I-stair exposed to weeks of rain and snow have had no problems.
13.Is i-stair accepted by the local building official?
Almost all of West Michigan code officials have seen and approved i-stair.
performed by Progressive Engineering Inc., ISO 17025 Accredited. Load Test Report by P-E-I is available from MPI Concepts Inc.
Down loadable Drill from City of Wyoming Mi. Fire Department:
Please share this with your crews. This is just one more of many reasons why we as the Fire Service needs to advocating for sprinklers every building!
Lt. John Shafer