Ventilation

When building a house or addition with a crawl space underneath, make sure to install a vapor barrier to prevent moisture infiltration into the floor system.

Welding inside of a shop or garage can create fumes. But they can easily be removed from the area by using industrial-type fans, or you can make your own from a recycled forced-air furnace fan. Check with the installers in your area for used fans; the cost may not be more than about $25, or they might even give you one. Cover the intake and all moving parts with heavy metal mesh, and run the power cord through a switch for easy on-off control.

Make sure that you have an adequate way to remove dust and fumes from your workshop. If your workshop has two windows that face each other, open one and put a fan that blows outward in the other. If not, an exhaust fan should be installed.

Clean warm-air registers, baseboard heaters, and radiators as needed. Make sure they are not blocked by furniture, carpeting, or drapes.

Never use a generator in enclosed or partially-enclosed spaces. Generators can produce high levels of CO very quickly. When you use a portable generator, remember that you cannot smell or see CO. Even if you can’t smell exhaust fumes, you may still be exposed to CO. If you start to feel sick, dizzy, or weak while using a generator, get to fresh air right away. Do not delay. The CO from generators can rapidly lead to full incapacitation and death. If you experience serious symptoms, get medical attention immediately. Inform medical staff that CO poisoning is suspected. If you experienced symptoms while indoors, have someone call the fire department to determine when it is safe to reenter the building.

Follow these safety tips to protect against CO poisoning: Never use a generator indoors, including in homes, garages, basements, crawl spaces, and other enclosed or partially-enclosed areas, even with ventilation. Opening doors and windows or using fans will not prevent CO build-up in the home. Follow the instructions that come with your generator. Locate the unit outdoors and away from doors, windows, and vents that could allow CO to come indoors. Install battery-operated CO alarms or plug-in CO alarms with battery back-up in your home, according to the manufacturer’s installation instructions. The CO alarms should be certified to the requirements of the latest safety standards for CO alarms (UL 2034, IAS 6-96, or CSA 6.19.01). Test your CO alarms frequently and replace dead batteries.

For bathrooms, ASHRAE 62.99 recommends that you exhaust 25 cubic feet per minute (cfm) with a continuously operating fan, or 50 cfm with a fan that you turn on and off as needed. Note that you might incorporate a bath fan into your overall ventilation strategy.

Remember that extreme temperatures can build in an attic without proper ventilation, especially with a dark colored roof.

Radon testing device(s) should be placed in the lowest level of the home suitable for occupancy. This means testing in the lowest level (such as a basement), which a buyer could use for living space without renovations. The test should be conducted in a room to be used regularly (like a family room, living room, playroom, den or bedroom); do not test in a kitchen, bathroom, laundry room or hallway. Usually, the buyer decides where to locate the radon test, based on their expected use of the home. A buyer and seller should explicitly discuss and agree on the test location to avoid any misunderstanding. Their decision should be clearly communicated to the person performing the test.

Attic ventilation is critical for not only summer cooling performance but also the longevity of the structure of your house.