Dry System for Barn with In-Ground Heating?

8/15/2022

I'm designing a fire suppression system for a new horse stables and barn. There is a hay loft above the stables, enclosed parking for farm vehicles, and a work area for food processing (mostly fruits).

The stables and hay loft are considered one space for fire suppression purposes. They will be heated (in-floor hydronics) to 10 deg C (50 deg F) so in theory, a wet system could be used. The heating system will use gas boilers connected to the local gas utility so I'm not too worried about losing heat. However, the stables will have barn doors around it (high infiltration) and the floors could be covered in hay/straw (reducing radiant heat from the floor).

So - would a dry system still be a prudent choice even though the space will be heated?

The project is in Southern BC, Canada. Our winter 1% design temperature is -6 deg C (21 deg F) but it rarely gets that cold. We currently use NFPA 13-2013.

Sent in anonymously for discussion. Click Title to View | Submit Your Question | Subscribe

10 Comments

Anthony

8/15/2022 07:30:29 am

This can only be answered by the HVAC engineer (if there is one on this project) This is a heat transfer problem not a fire protection one.

I think a more important question is how often will the doors be open in cold weather. This might be best thought of as a loading dock environment where the area will have large doors openings rendering the heating moot.

Chris Nelson

8/15/2022 08:07:05 am

Anthony said it correctly. Ask your HVAC engineer. I just finished a project for a Fire Department where the apparatus bay is being heated by radiant floors and my hvac engineer couldnt promise that the space could be heated above 40F if the doors were left open so we went with a dry system to protect the system and the space.

Dan Wilder

8/15/2022 08:10:34 am

As Anthony said, this isn't our issue to confirm. The question to the owner is can the roof level fire protection system be maintained at or above 40°F (~4.5°C). While the floor may be heated, radiant transfer (or lack there of), loss through open doors, roof/wall level insulation, air currents...all play into those calculations.

If in doubt, provide the dry system or have the owner sign off that the space will be maintained (against your professional opinion) and move forward with the project with either installation or walking away due to liability.

Jesse

8/15/2022 08:18:14 am

All 13 says is that wet-system components must be kept at or above 40-deg F. So it really seems to be a questions for your HVAC guys. If they affirm that the system can be kept at 40-deg F or above go with a wet system.

Glenn Berger

8/15/2022 08:20:25 am

It appears that you have done due diligence and that the best solution is a dry pipe system, should not be a disputed point.

Gregory Merryfield

8/15/2022 12:21:35 pm

Agree with Glenn and Michael, Alex, et al.

Even LEED buildings that have wonderful heating efficiencies sometimes will have spaces (where sprinklers hide) that are too cold. The heating system in this instance sounds wonderfully efficient for keeping the animals warm and not necessarily a wholistic building heating system for humans, or water filled piping.

Michael

8/15/2022 08:41:28 am

This is definitely a dry system application.

Albert

8/16/2022 09:20:42 pm

x2.

But further, what’s the price point? The risks and benefits of wet vs. dry? And present this to the owner.

If it were my barn I would absolutely opt for the dry system. And I’m sure the owner would agree. Feed is expensive at harvest. Imagine what it would cost to replace all of it in the dead of winter, and transport it, when market supply is lowest and the animals demand is urgent and critical. Oh and those wet bales, they’ll burn a barn down.

Dean Melanson

8/15/2022 08:42:23 am

There is no way the system could be guaranteed to be kept at the required temperature under the conditions described. While gas equipment is not directly affected by power loss, the pumps, automatic ignition and thermostat all need electricity to function. A dry system is appropriate.

Alex

8/15/2022 11:06:07 am

Hi,

I would say a dry system should be installed.

Thank you,
Alex

Dry System for Barn with In-Ground Heating?

Leave a Reply.

ALL-ACCESS

SUBSCRIBE

COMMUNITY

YOUR POST

PE EXAM

FILTERS

ARCHIVES

PE PREP SERIES