Air Sealing Solutions for Sprinklers
Air sealing. What is it? Do we have to do it? How do we do it? These are just some of the questions that come up when discussing the topic of air sealing sprinklers.
As sprinkler systems become more common in single family housing and the energy codes requirements increase, properly air sealing sprinklers becomes a prime concern. Fire sprinkler systems result in additional penetrations in the air barrier, whether the sprinklers are side wall or ceiling mounted. Air barriers are systems of materials designed and constructed to control airflow between a conditioned space and an unconditioned space. The air barrier system is the primary air enclosure boundary that separates indoor (conditioned) air and outdoor (unconditioned) air.
The International Energy Conservation Code (IECC) states in Section R402.4.1.1 that the components of the building thermal envelope must be installed per the requirements of Table R402.4.1.1. This table states, “concealed fire sprinklers shall only be sealed in a manner that is recommended by the manufacturer. Caulking or other adhesive sealants shall not be used to fill voids between fire sprinkler cover plates and walls or ceilings.” The commercial provisions have a similar requirement. Section C402.5.1.1 for commercial buildings states, “Penetrations in the air barrier shall be caulked, gasketed or otherwise sealed in a manner compatible with the construction materials and location… Sealing of concealed fire sprinklers, where required, shall be in a manner that is recommended by the manufacturer. Caulking or other adhesive sealants shall not be used to fill voids between fire sprinkler cover plates and walls or ceilings.
Penetrations through the air barrier are going to be air-sealed with either caulk, tape, or foam. Here is where we begin to run into problems, and you must conduct research to determine with which materials to air-seal. Residential sprinkler piping is most often a non-metallic material and understanding which materials are compatible with the sprinkler components is vitally important to extend the life of the piping and maintaining manufacturer warranties. Throughout the years, the industry has painfully discovered that following the manufacturer’s installation instructions is critical. There is a range of chemicals (present in caulks, the adhesive on tapes, foams, etc.) that can have negative effects on non-metallic materials that can lead to failures.
So, how do we properly air seal sprinkler systems? The biggest concern is the field applied seal around the sprinkler penetration through the drywall. That concern is valid. Sealing this penetration can damage the sprinkler and lead to malfunction. Also, the small cavity between the cup and recessed cover plate cannot be sealed. Sealing this void will cause the plate to not drop and activate. See Jeff Hugo’s article from the 2012 Nov/Dec edition of the National Fire Sprinkler Magazine titled, “Caulking Fire Sprinklers for Energy Code Compliance,” for more information on issues that arise caused by rogue solutions. Check with our many sprinkler manufacturer members to determine what they recommend and have available.
It is important to determine who is responsible for the air sealing work and the scope of work is detailed in the contract. Air sealing, insulation and compliance with an energy code is not the expertise of the fire sprinkler contractor; it is very important to coordinate with the responsible insulation contractors and builders. There are many code compliant methods to properly seal the sprinkler penetrations. Insulation contractors need to have special concern to ensure the air sealing product system is compatible to non-metallic piping materials. While fire sprinkler contractors and code officials are well versed on the compatibility and sprinkler operations, they should spread the word on their jobsites to avoid jeopardizing life safety systems. Energy codes are new in a lot of areas of the country, so be aware of the following:
- NFPA 13 (2019), Section 220.127.116.11 and 18.104.22.168, NFPA 25 (2020), Section 5.2.1, IFC Section (2018) I101.2, IECC (2018) Section C402.5.1.1 and Table R402.4.1.1 all prohibit use of caulk on fire sprinklers and require replacement when coated.· Energy codes may or may not be in effect at the time of construction, but common practice might be to caulk all gaps in building materials.
- Existing buildings where NFPA 25 inspections are being performed may be updated, renovated, or repaired in-between inspections to obtain energy credits. Be on the lookout for newly caulked sprinklers.
- Install fire sprinklers so the escutcheons and cover plates fit correctly against the wall or ceiling. Leaving loose escutcheons and gaping cover plates will encourage caulking or adhesives after leaving the site.
- Consider sidewall sprinklers. Interior sidewalls are usually not part of the building envelope, therefore exempt from air sealing.
Energy codes are being developed and adopted at a quick pace. We are seeing energy conservation at new levels all throughout the world and fire protection systems need to function properly to protect lives and property before energy conservation can be measured.