Fire walls general requirements

[arango]

Greetings,

Im' an electrical engineer and I'm not sure if this is the right place to ask this, but i'll do it anyway, I'd like to know if anyone can help me with the necesary requirements for fire walls on buildings, I'd really appreciate it.


Thanks.

 

[concretemasonry]

Codes will set the fire rating required for the specific application/use.

If the wall is concrete masonry, the basic criteria is the type of aggregate and the "equivalent thicknes" (the amount of material in the wall), which is the percentage of solids times the actual masonry unit thickness. There are tables available in the NCMA Tek Notes(ncma.org). You can also refer to UL designs for specific or unique wall assemblies.

Generally, ratings may also be calculated by adding the ratings of specific layers applied to the masonry. The ratings may also be increased by filling the cores with approved materials (vermiculite, sand, grout).

Dick

 

[jike]

Building codes generally set the required rating. This depends upon the material used in the construction, fire protection (ie, sprinklers) the number of occupants, the use of the structure and square footage. For instance a nursing home, hospital or school will have more stringent requirements than an industrial building.

Once you have determined the location and rating then the details of the construction need to be determined. Codes now require that if the structure collapses due to fire on one side of the wall, that the wall remain standing. This gets into some interesting structural considerations. Different types of fire walls include free-standing, double fire walls, tied walls, self releasing, one way walls, etc.

FM, NFPA and the Canadian codes all discuss various details of construction. It is very important that each discipline understand their specific requirements.

 

[msquared48]

If I am not mistaken, I believe that the ICBO Standards have a lot of ratings for different fire wall systems.

Mike McCann
McCann Engineering

 

[msquared48]

Pardon me - I was thinking of the UBC Standards...

Mike McCann
McCann Engineering

 

[arango]

I'm sorry, but I'm not familiarized with those standards you're mentioning, I'd appreciate if you can give me a hint about where I can get them.


Thanks,

 

[concretemasonry]

The codes, IBC, IRC, UBC, CBC, etc., will give the fire resistance requirements based on the use or occupancy.

The codes have tables or make references to the organizations that establish the performance properties for materials or assemblies. The codes usually rely upon these groups to do research and provide documentation for the properties.

Some associations have a history of well documented tests and reports. These are usually long term collections of test results and interpretation depending on raw materials. UL has a good listing of unique assemblies to be used as a reference.

Since you posted in the concrete engineering section, I assume you are concerned with concrete or concrete masonry fire walls. Since the aggregates are local, you should determine what the locally available types are. In some cases, changing aggregates (from normal weight to lightweight, as an example), can result in a wall thickness that can be less or give the option of a different assembly.

Consult the applicable local building code (and effective date) for the requirements. An owners insurance carrier could also offer lower rates for different wall assemblies.

For product information, contact the NCMA (ncma.org) for concrete masonry, the precasr association for precast walls and your local producer of wall panels for the ratings and suggested construction details.
For concrete masonry

 

[dik]

As an aside... firewall should generally be constructed so that they continue to act as firewalls in the event one side or the other side collapses in a fire.

Dik

 

[arango]

Thanks for all,

You have been a great help for my research, i'll start checking theses codes you named.