KEES louvered penthouses are rooftop enclosures comprising four louvers with a covering. They block rain and snow while allowing air to pass through, providing ventilation for a building and protecting HVAC equipment, mechanical systems, or stairwell access points from weather, debris, and pests.
KEES simplifies sizing an intake or exhaust louvered penthouse with our in-house performance chart, letting reps identify the right size product for our clients’ needs.
How to size an intake louvered penthouse
Intake louvered penthouses draw in fresh air from outside the building while stopping rain and snow from coming along with it. When a client comes to KEES to specify an intake louvered penthouse, they know the size of their roof opening and the desired airflow in cubic feet per minute (CFM). KEES reps measure that information against our Penthouse Performance Chart:
For example, if a client’s desired airflow for their intake louvered penthouse is 2,400 CFM, that value corresponds to a 24”x24” throat opening with five tiers at a velocity of 600 feet per minute (FPM) and a pressure drop of 0.07 in. wg.
That is not the only option for our hypothetical client. A 18”x24” throat opening with four tiers at a velocity of 800 FPM and a pressure drop of 0.09 in. wg. would achieve the same 2400 CFM. It would result in a smaller penthouse that requires more energy to move the same amount of air, but that tradeoff may be worth it for our client.
How to size an exhaust louvered penthouse
Exhaust louvered penthouses allow air to leave the building while protecting roof openings from pests, weather, and debris. Like with an intake louvered penthouse, our client will come knowing their desired CFM and roof opening size. The same Penthouse Performance Chart can be used to size exhaust louvered penthouses by reading the bottom row of pressure drop values.
Our hypothetical client’s options for an exhaust louvered penthouse at 2,400 CFM are the following:
A 24”x24” throat opening with five tiers at a velocity of 600 FPM and a pressure drop of 0.06 in. wg.
A 18”x24” throat opening with four tiers at a velocity of 800 FPM and a pressure drop of 0.10 in. wg.
Why is it important to properly size a louvered penthouse?
A properly sized louvered penthouse will operate at the intended performance. An improperly sized louvered penthouse will not be as cost-effective, will underperform, and may take up valuable roof space.
Too Small: A louvered penthouse that is too small for the roof opening will speed up air velocity, letting rain, snow, and other forms of weather into the building.
Too Large: A louvered penthouse that is too large for the roof opening will be an unwarranted expense, as well as an inefficient use of roof space—where square footage can be in high demand.
KEES Simplifies Sizing Louvered Penthouse for Any Installation
Whether you need an intake or exhaust louvered penthouse, KEES makes it simple to review your options. We offer a large range of possible sizes to work with any roof configuration. Are your size or airflow requirements not on our chart? Get in touch with a KEES rep for a custom penthouse built to your exact size and CFM specifications.