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Recent Blog Posts

Accessible and adaptable kitchens in multi family units

I had a question about the heights on the kitchens.

Per chapter 11A do we need to have the height of the counters at 34", do all units have to have the counter height at 34" or only 5% accessible units?

Or can they be at 36" as they will have granite counter top and the exception 1133A.4.1 #2.


Metal Stud Fire Walls

Why do we allow a wall to be classified as firewalls when it is significantly different from the tested configuration?

Typical, Metal Stud Assembly Description

"1-1/4 in. wide by min 3-5/8 in. deep fabricated from min 0.020 in. (25-gauge) thick galv steel, attached to floor and ceiling with fasteners spaced 24 in. OC max." (With 5/8 Type X gypsum wallboard both sides etc.)


At the 1800-degree temperature attained during ASTM-E119, Thermal Expansion causes metal stud to expand 1/4 inch per foot. That three inches of expansion, on a twelve foot stud causes the stud to bow laterally twelve inches.

How can they say that a wall constructed with 3-5/8", 16-gauge CSJ (1-5/8 inch) studs placed 16 inches on center will respond the same in ASTM E119 fire test, Actually they don’t.


The following was copied from UL description of ASTM-E119



Significance and Use
These test methods are intended to evaluate the duration for which the types of building elements noted in 1.1 contain a fire, retain their structural integrity, or exhibit both properties during a predetermined test exposure.

The test exposes a test specimen to a standard fire controlled to achieve specified temperatures throughout a specified time period. When required, the fire exposure is followed by the application of a specified standard fire hose stream applied in accordance with Practice E2226. The test provides a relative measure of the fire-test-response of comparable building elements under these fire exposure conditions. The exposure is not representative of all fire conditions because conditions vary with changes in the amount, nature and distribution of fire loading, ventilation, compartment size and configuration, and heat sink characteristics of the compartment.
Variation from the test conditions or test specimen construction, such as size, materials, method of assembly, also affects the fire-test-response. For these reasons, evaluation of the variation is required for application to construction in the field.

Mezzanine Fire Protection in a Type 1A Towwer

We have an existing 52 story Type 1A Building.


All floor assemblies, the roof, columns and substructures are protected by SFRM. Per Table 601


My 52nd floor is a 30 foot high space, we are proposing an intermediate mezzanine. 


Does the mezzanine structure (deck, beams and columns) also require fire proofing.


Technically the mezzanine is not considered a new floor, however it is oocupied space.


I could not find a code reference for this condition.

Thanks in advance for any insight.

Fire Protection for Mezzanines

I have an existing 52 story Type 1A Building. 

All floor assemblies, the roof, columns and substructures are protected by SFRM.

My 52nd floor is a 30 foot high space, we are proposing an intermediate mezzanine. 


Does the mezzanine structure (deck, beams and columns) also require fire proofing.


Technically the mezzanine is not considered a new floor, however it is oocupied space.

Access to Roof

In a 24 story R-2 (apartment) building in California, permitted under the 2001 CBC, we have a landscaped roof terrace that can hold an occupancy load of 190 persons.  It is furnished for parties with barbecues, chairs and tables.  We have three elevators and two fully compliant exit stairways up to this roof, one stair is accessed directly from the terrace, the other stair is accessed through a glass door into a small corridor that connects to the elevator lobby and the exit stair.  Residents can access the roof terrace through the glass door which is equipped with a power door opener, activated from both sides of the door, for the handicapped.  The doors to the corridor and both stairs open in the direction of egress travel (from the terrace to the stairway) and are equipped with panic exit devices.  The Owners wanted to control access to this roof amenity so they installed a card reader at the inside of the glass door with an electric strike that is automatically retracted when the fire alarm is activated.  The Fire Department will not grant a Final Occupancy Permit because they say the glass door must be unlocked for any emergency, not just a fire, quoting Section 1008.1.9 from the 2013 CBC which says that "egress doors shall be readily openable from the egress side without the use of a key or special knowledge or effort."  The comparable section of the correct 2001 CBC [1003.3.1.8] says "exit doors shall be openable from the inside without the use of a key or any special knowledge or effort."  We do not think the inspector is even aware of the unfortunate language in the 2001 code that could be construed to support his point of view, but citing the current code he seems to be fixated on the need to keep this door unlocked so occupants of the building can seek refuge on the roof if they ever want to.  He seems to regard the door as a "dual egress" function, although he has not said as much. The owner is willing to install an override switch at the door that retracts the strike whenever the switch is activated, with an alarm sounding at the security desk downstairs.  The fire inspector is not confident that this will be acceptable to the Building Department so he is asking us to prepare new drawings to be submitted to the city for permit, showing this configuration of locks, card readers, fire alarm override and manual override with alarm.  If they accept this, he says he will allow it.   Our position as the architects is that the door is code compliant now, even with a card reader.  The CBC does not appear to require that the door to the roof be unlocked nor does it forbid the door from being locked.  It only requires that it be openable in the direction of egress travel, which in this case is from outside to inside.  Is there anything in the code that I can use to convince the inspector that this is the case and we can leave the door as it is with a card reader on it, controlling access to the roof, without adding the manual override and especially not going back in for a permit revision? 

Need info on Building Codes in Portugal

Hello, I hope I am not too much of a noob asking this, but I'm working on a project where we are designing a facility in Portugal, and I've ran into a bit of a dead end having to do with which building codes I should be aiming for with respect to platforms, guardrails, ladders and stairs. This is meant for an industrial application. I am able to follow IBC code pretty well, but when I get to designing the ladders, I find a hole in IBC code where I find no specs on ladder designs, i.e. cages, rung spacing, connection details, etc. Where would be a good resource to find out which codes I have to follow and can anybody give me some insight into anything I need to do differently than with OSHA building codes?


Thanks for your consideration