What does a Garden Gnome do when she is not gardening, in the kitchen or doing genealogy? Well the answer might just surprise you so read the entries to find out more. This blog focuses on everything we do to make our house a home. There will be a strong emphasis on home energy efficiency and do-it-yourself (DIY) projects. At the same time there will also be crafts, knitting and crocheting projects along with any other little tips we do to create that down to earth, I want to be here home. Please enjoy your visit :)

Wednesday, November 30, 2011

Sources of Air Leaks in a House

The cost of energy is consistently rising so energy efficiency is ever more important.  Air leaks in your home can cost you hundreds of dollars a year in energy costs and yet they are one of the easiest to remedy with low cost materials and DIY projects.  For example, a 4  x 300 ml package of 25 year durability interior/exterior acrylic caulk costs $8.97 at Home Hardware.  Simply using one of the tubes to seal cracks could save you the cost of the caulk in less than a month during the heating season.  Just imagine the savings if you used all four tubes!  Chances are good that you may not have to use all four tubes of caulk depending on how well sealed your house is already.  For example, I likely used four tubes of caulk in our third house but closer to twenty tubes in our last house, and I estimate this house will need less than four.  The difference being the age and design of the houses as well as whether the previous owner did any sealing. 

Cracks and crevices are not the only source of air leakage in a house.  Improperly weather stripped door and windows can cause a significant amount of air leakage.  Faulty seals on refrigerators or freezers can cause air to leak out of either which causes the appliance to use more energy which translates into paying more on your hydro bill.  Electrical outlets, switches, and ceiling/wall fixtures can all be sources where cold air can leak into the house.  Our hydro panel was located on an outside wall in main living area.  On a windy day, enough wind came in to move the mirror hung over it!  Fireplaces can literally suck heat air from the room, ultimately costing you more in heating costs.  Gaps around wires, cables and pipes entering the house can be a significant source of air leakage.  A gas pipe had been installed in our fourth house but had not been sealed properly allowing a gap big enough that rodents could get in!  Bell installed our satellite tv here and I specifically asked the technician if he had caulked around the cable.  He said he had but he obviously didn't as I found out the first windy day where the wind was hitting that side of the house.  Exhaust fans and clothes dryers both can let in a significant amount of cold air.  One solution to this problem is to replace regular vent covers with the Braun Eco-Vent.  This specialized insulated vent cover has a ball closure that opens to allow exhaust air out but seals when not in use to prevent cold air from entering the vent.  Your HVAC ductwork may have seams and joints that aren't sealed causing the loss of hot or cold air when in use.  Seal any you can with aluminum foil duct tape.

It is possible to use temporary air leakage blockers such as door snakes, removable caulk, heavy quilts or blankets, towels, shrink plastic, and cardboard secured with removable tape.  These are ideal when you discover a bad air leak that can't be immediately repaired.  For example, today it is extremely windy with driving torential rain.  I discovered the range hood that desperately needs replacing is pouring in very cold, damp air.  I taped a piece of carboard to the filter just to stop the cold air from coming it.  It is only a very temporary measure that quickly solves the problem until the wind dies down and obviously one that can't remain if using the stove.  What this means though is the flapper on the range hood that prevents cold air from entering the house is broke.  Since we are replacing the range hood the problem will be solved anyway.  If using a temporary blocker, do not create a fire hazard or block exit routes from your home in the event of an emergency. 

Before embarking on sealing your house, be aware that a house can be sealed too tightly creating problems with indoor air quality and the proper operation of combustible appliances (eg. gas fireplaces, gas furnace, gas water heater, gas ranges).  Be sure all combustible appliances are venting properly before and after sealing.  Under normal daily activities, there should be enough fresh air entering a house via outside door during entry and exit.  A tightly sealed house may require an air exchanger.  Our new house has a Lifebreath HRV (model 150Max) that is set on a 40/20 cycle.  For twenty minutes each hour the HRV brings in fresh air from outside while exhausting stale air.  Also be aware that in tightly sealed homes it is even more important to avoid using toxic household cleaners and anything containing VOCs (eg. some paints, household cleaners).  It is important to use controlled air exhaust (eg. range hoods, bathroom exhaust fans, HRV,) methods to reduce indoor air pollution, ensure sufficient fresh air entering the house and to ensure combustible appliances have ufficient oxygen for proper operation.  It is a good idea to have an air pressure test done on your home before and after sealing as well as have any combustible appliances checked for proper venting before and after sealing.

Garden Gnome