How Many Roof Vents Do I Need Uk

They should be divided equally between inlet and outlet vents and they can be used in any combination that will work with your roof s design.

How many roof vents do i need uk.

Near ridge of the roof. Federal housing authority recommends a minimum of at least 1 square foot of attic ventilation for every 300 square feet of attic floor space evenly split between intake and exhaust. Calculation for the ventilation of interiors this table is an example of how to calculate the ventilation of the interiors. I have found this combination usually sorts out most roof space condensation.

For example if your roof structure has a ventilated area of 150 m 2 and you wish to use the lomanco bib12 unit you would need three units for an efficient and balanced ventilation system. How to determine how many vents you need the rule of thumb used to determine the number of roof vents to install is one for every 300 square feet of attic area if your attic has a vapour barrier and one for every 150 square feet of attic area if the attic does not have a vapour barrier. Based on your 1100 sq. Their advice will be specific to your property.

Use the calculator below to find out how many exhaust and intake vents you will need on your house. And this guideline you ll need a minimum of. A competent roofer will advise you how to optimise the ventilation in your roof without adding too much if you install too many roof vents or the wrong type of ventilation this can make your roof more vulnerable to leaking. In this country there seems to be two reasons for fitting roof vents.

As a general rule your roof needs 1 square foot of vent area for every 150 square feet of attic space. This is based on m3 h. Roofing superstore s full range of roof vents can be found here. One is if the roof is leaking then the movement of air will help dry it out the other that water vapour created inside the home will rise through the ceilings and holes in the ceilings and condense on the cold roof timbers perhaps a dozen or so times a year with the potential to create wood rot.

For example if you have 1200 square feet of attic space you should need at least 4 air vents to ensure proper ventilation. For most situations a simple 2 vents front and back seems to be a good starting point some roofers favour two low and one high per elevation making a total of 3 front and 3 back for example.