Keeping Heat in the Home

wallHeat loss is a tragic thing in the winter. Your furnace puts in so much effort to keep you warm, using fuel to start a fire, burning the heat exchanger, heating the air inside, and blowing that air throughout your house. But it’s all for nothing if your house has a serious case of heat loss. By this phrase we’re referring to a house in which through one or several means, warm air is escaping the house and cool air from outside is sneaking in to a degree significantly above what is normal and expected.

Because it’s not like there shouldn’t be any exchange of air between the outside and the inside. There’s no such thing as a perfectly insulated house, especially when you consider the fact that people are going in and out of the house throughout the day. But there are several inconsistencies in insulation that can cause a significant air leak in the house which can cause your furnace to work harder and your home to be less comfortable. Some of these heat loss culprits may be more obvious than others. In this tip we’re going to investigate many of the more common causes of heat loss including some that you may not have considered before. This way you can be armed with the knowledge of what could be possibly costing you comfort and money as you’re heating in Austin this fall and winter season.

Attic and Roof

By some estimates, it’s likely that about 25% of the heat that’s escaping your house is doing so through the roof. The way warm air escapes through the roof is by the process of convection. The heated air within the house is distributed throughout and eventually rises up toward the attic. Once it comes in contact with the cold roof, heat slowly dissipates through the process of convection. The same thing happens with a cup of hot coffee. If left alone, the cup will not stay hot for long because heat is absorbed and exchanged with the surrounding air.

Most people solve this problem the inefficient way. They increase the setting of the thermostat to a higher temperature. This creates the effect of an increase in energy costs. The second option is to just prevent the heat from escaping the roof in the first place and this is the most cost-effective way of sustaining warmth in a living space. Roofs are constructed to include an insulating material to prevent heat loss; however, improper installation of this material and worn out insulation could lead to wasting heat costs during winter months.

There are decisions to be made before one can properly insulate the attic of a house. First, you must decide what the attic will be used for. Will it be just a storage space or will it be turned into a loft? And you have to decide what type of material to be used in insulation. Three of the more effective and commonly recommended types of insulation are fiberglass, foam, and cellulose fiber. All three of these will accomplish the task of safeguarding the roof from the process of convection, conduction, and radiation that causes roof heat loss.

Cellulose fiber has the benefit of being one of the cheapest types of insulation and is also treated to be flame retardant. Foam is an effective preventer of convection and comes in two forms: foam boards that will have to be cut down to the required size before installation; and liquid which can be sprayed directly into the loft or attic area. Fiberglass is one of the most effective insulators available and can be cut and used in a wide variety of shapes and sizes.

Thermal Bridging

It’s a well-known fact that most of the loss of heat in your home is going to be through the walls. This only makes sense as the walls take up the most square-footage of your home and are the biggest contact point between the inside and outside air. But less well known is the fact that even with well insulated walls there can still be a significant amount of heat loss due to a process called thermal bridging.

This is the process by which a more conductive material enables heat flow through walls and insulation. It’s a much larger cause of energy loss than often anticipated. Thermal bridging usually happens through studs and framing in the walls, which lower the overall R-Value of a wall and aid loss of heat to the outdoors in winter. Thermal bridging is most directly addressed through the addition of a thermal break by adding foam or other low-conductivity materials to the external layer of wall sheathing or adding a layer of insulation directly around studs. This will have to be done by a professional and is not recommended as a DIY project due to the amount of sophisticated procedures required.

Reducing thermal bridging in the walls of your home can have a significant impact on heat loss and in the end can save you money in energy costs. This might be a solution that comes up during an energy audit done if it is found that you’re losing heat to a significant degree due to thermal bridging.

Exhaust Fans

Another less often considered cause of heat loss in the home is exhaust fans. Exhaust fans serve different purposes depending on their location but they all serve as a connection between the outside air and the inside environment. In the bathroom they help remove steam and moisture from the room during and after a shower which helps prevent excess moisture from causing rotting and mold growth in the walls. In the kitchen an exhaust fan can help remove steam when boiling, clear away strong smell faster, and remove smoke in the case of something burning.

These are all useful purposes but they have the drawback of requiring a break in the insulation of your house through these vents that lead outside. There are ways to mitigate this effect, though, and with the proper design, the heat loss that happens due to exhaust fans can be reduced. Every exhaust fan system should have a backdraft damper installed where the exhaust duct exits the roof or exterior wall. This may be a factory-installed piece that came with an exhaust fan kit, or it could be a separate part selected by the installer. There are also several different styles of backdraft dampers, and some are more reliable than others.

It’s a good idea to know exactly where your exhaust ducts exit and how your dampers work, because there are several things that can go wrong with them. For example, a windborne twig could get jammed in a hinged damper flap, holding it open even when the exhaust fan is turned off. This would provide a wide-open entrance for cold air, pests and debris. Over time, dampers will suffer broken parts or the flaps might get rusted and stuck open. Have these checked out in early fall and whenever you clean your gutters, and replace them when the time comes.

Even if your damper is in good shape, you may want to consider replacement if you notice abnormally cold air below your exhaust fan. Not all dampers are created equal, and some may allow too much cold air to seep in even when they’re functioning normally. If you’re unsure whether replacing your damper could make a difference, ask a cooling and heating professional.


In a stroke of symmetry, it is often cited that around 10% of the heat loss to be expected in a home is through the part of the house opposite of the roof, the floor. For floors it is important to ensure sufficient insulation between the ground and the floor surface. In new buildings, sufficient insulation is installed during the construction and in older buildings, insulation layers can be laid on existing floor surfaces.

Old wooden flooring or bare concrete flooring, even in smaller places like utility rooms, can contribute to heat loss. While warm air rises it can easily escape and cold air can easily make its way in without a barrier between the cold floor and your warm home. Invest in carpeting to create an effective layer of floor insulation, and buy draught excluders to prevent cold floor-level air from travelling throughout your home.

Related to floor heat loss is that of the spaces just beneath the floor, namely crawlspaces and basements. Now, most homes in Austin don’t have basements but crawlspaces may still be an issue for some of you especially when it comes to older houses. This is especially the case in very old homes because they often have field stone foundations and cramped dirt crawlspaces. In many of these spaces, especially inaccessible crawls, the foundation is often not sealed properly to the outside. This can either be solved by digging away the soil from the outside and repair the foundation, or by doing the same from the inside. In field stone basements, often the wood footings of the house do not sit squarely on the stone foundation, resulting in numerous little gaps. Using spray foam in a dispenser can is a quick and simple way to fix these little holes.

Heat Loss Spots and Heating Repair in Austin

These are just a few of the many potential causes of heat loss in the home during Austin’s heating months. Some of these, like the floor and roof, may have been more obvious, and some, like thermal bridging and the exhaust fan, may have been less. Other common causes of heat loss include poorly insulated windows, doors, and chimneys. The best way to look into and solve these issues is to first get a professional energy audit done so that the exact spots in your home that are leaking heat can be identified.

And if you ever have any problems with your heater, whether it be a boiler, furnace, or heat pump, don’t hesitate to call a local Austin heater repair expert like AC Express. We operate throughout the Austin area, from Cedar Park and Georgetown to Lago Vista and Lakeway. Our experienced technicians can get you the heater repair in Austin you need as soon as you need it. Call today!