On this episode of Dr. Energy Saver's "On The Job" series, Larry Janesky and his crew were called in to install a high efficiency heating system - to effectively heat this 9,000 square foot commercial garage. In order to do so, a radiant heating system is designed with loops of radiant heat within the floor slab, along with a high energy-efficient gas boiler to heat the fluid that goes through the system.
Part of the strategy to improve energy efficiency is to make sure that the heat isn't lost to the ground - through both the slab downward and outward through the foundation walls. As soon as the foundation walls and shell are constructed, Dr. Energy Saver can finally get inside the building to begin the construction of the radiant heating system.
To start the process off, radiant loops are laid out evenly across the flooring of the commercial building. The next step involves laying out a 6-inch concrete slab over the radiant loops. This part of the installation process soon becomes a challenging task because the concrete mixer is unable to drive across the surface with the radiant loops embedded.
In order to install the concrete slab, a pump truck from outside the building is used to pump concrete into the building, laying the slab out. Once installed, the heating from the radiant flooring will keep the slab nice and warm, increasing the thermal mass at the bottom of the building and ultimately radiating the heat upwards to warm the contents within the building.
Commercial garages have huge doors that need to be opened frequently - several times a day - so the challenge was not only to heat the 9,000 square foot space but prevent all the heat from escaping when the doors open. This method of heating is especially effective for this type of building because of it's ability to store thermal heat within the slab - minimizing significant heat loss from the constant opening and closing of the garage doors.
To prevent the radiant heat from escaping outside through the walls and floors of the commercial building, Dr. Energy Saver used two approaches. First, the foundation walls were insulated on the outside of the building with 4-inch rigid foam boards and second, the concrete slab applied over the radiant loops were built 6-inches thick. The thick floor slab creates enough thermal mass to conserve the heat on the slab when the garage doors open, allowing for a quick recovery when the doors close.
Opting for heating the building with a high-efficiency radiant floor system, the radiant loops were laid out underneath the concrete slab in zones.
The 9,000 square foot slab was divided into five heating zones, each zone is connected to a variable speed circulator, which can be individually adjusted to control the speed in which the water circulates in the radiant loops.
The radiant floor system relies on a high-efficiency Mod Con (Modulating and Condensing) Boiler. A self-modulating system like the one used, has the ability to increase and decrease the opening of the gas valve depending on how much heat is needed. On warmer days, the pilot flame burns low, and on cold days the unit will burn more gas to produce more heat. This saves a lot of energy because the unit is not running full blast at all times.
Highly-efficient condensing boilers like this one also have a secondary heat exchanger that extracts as much heat as possible out of the exhaust gases. That heat is then used to heat the building rather than escaping outside. The exhaust gases in these units are so unbelievably cool that they can be vented to the outdoors using conventional PVC pipes!
With the radiant heating system installed within the flooring - the heat will remain down low, keeping the floor warm and letting the heat rise - to warm the contents and people within the building. This heating system will improve the comfort for those that work within the building, while, also keeping the costs low to operate!
After the upgrades of the building were completed, Dr. Energy Saver returned to test for air leakages. As with any new construction, not every air leak is fixed the first time around. In this case, gaps around the garage doors, and all around the perimeter of the roof were allowing cold air in and hot air out and had to be air sealed and insulated using spray foam. If you want to make your home or commercial structure more energy efficient, we can help!
Contact your local Dr. Energy Saver today to get started!