by Charles Hendricks | Feb 5, 2014 | architecture, Building Science, Harrisonburg Architect, Indoor Air Quality
I get questions on a regular basis about home comfort and efficiency. This question came from someone who read my blog and wanted to get their HVAC system adjusted and wanted to know who to call.
“Our house is quite cold this winter and our energy costs are pretty high – I suspect our heating system is not very efficient, and I am looking to hire someone to come identify and fix any problems. Who should I call?”
The easy answer for your HVAC system is to call Jay Monger at
Excel HVAC. He will get your system right.
The path that I would suggest instead:
Get an
energy audit from
Building Knowledge so that you can develop a comprehensive approach to make your home efficient. His findings will probably be along the following:
You HVAC system is most likely oversized, insulation inefficient in the attic and basement / crawl space, hot water pipes not insulated, and there is a strong need to air seal your home. Since HVAC systems are expensive, I would first air seal your home, then insulate, then adjust the HVAC system.
To air seal a typical home, you could caulk and weather seal all the gaps and cracks in the thermal envelope (electrical outlets, around recessed lights, attic access, doors and windows, and around HVAC boots). The big holes will most likely be the band board (where the floor joists hit the outside walls). These are best sealed with spray foam insulation (open cell not closed cell).
Then, most likely your attic does not have enough insulation and probably not air tight insulation. This is a hard decision to make – to fix the air tight issue you usually need to remove the insulation that is already there. Most people, including myself, don’t like throwing away something you already paid for. So typically, you just accept the air leakage in the attic insulation and add another layer of insulation on top of what you have there. Code minimum is R-38, but I would suggest a minimum of R-50, but like to see R-72 if budget and space allow.
Basement renovation
A basement / crawl space is another good place to attack if the space is not finished. We often find insulation in the floor system above. It should be on the walls for better performance. The band board is often not insulated at all, this area should be sprayed foam.
Once you get the house as air tight as possible and have insulation added in appropriate places, then the HVAC system can be adjusted as needed – perhaps just adding a fresh air exchange depending on how tight you get the home. It might also need some dampers added to get the right amount of air into the right rooms.
For insulation – if you want to skip the energy audit – call Ken Wells at
Elite Insulation. For a couple thousand dollars, he can get your home WAY more comfortable even before the energy audit. He understands building science and is fair with his pricing.
If you have questions about your home, let us know!
by Charles Hendricks | Jan 28, 2014 | architecture, Building Science, Harrisonburg Architect, Indoor Air Quality
Many new homes are taking advantage of that space above the attached garage for an additional bedroom / bonus room space. It was made possible by the invention of the attic frame truss that is able to span a two car garage and provide a 12′ wide usable room above. However, most bonus rooms have a problem – they are uncomfortable. You can see in this image that a builder has addressed the problem by adding an ugly through wall heating / air conditioner. This will make the room comfortable, but adds to your electric bills, does not address indoor air quality issues, and is usually noisy – not to mention ugly.
This bonus room space is a nice add to the usable space in a home, but has indoor air quality and comfort issues. This is due to the difficulty in getting them air tight as well as difficulty getting supply and return air into the space. A bonus room above the garage needs extra attention from the insulator. In order to get it air tight and efficient, they need to use a LOT of caulk or an open cell spray foam solution. This will also protect against the air infiltration from the garage below. Good planning may also allow for HVAC ducts, supply and return to reach the room through the knee walls. This all needs to be carefully planned and thought through in advance of construction to get it right.
While I prefer this space to only be used for storage in a detached garage, sometimes the lot demands it be attached. If you do take that route, be sure to plan for comfort and indoor air quality solutions that will allow you to sleep knowing you have protected your family.
by Charles Hendricks | Jan 27, 2014 | architecture, Building Science, Harrisonburg Architect, Indoor Air Quality
Back to the building science questions. What can you tell me about this room just by looking at the picture? Also, how do you fix it?
by Charles Hendricks | Jan 22, 2014 | architecture, Building Science, green term defined, Harrisonburg Architect, Indoor Air Quality
Do you need a dehumidifier? We live in a mixed humid climate in Virginia and so often, you hear from the heating and cooling contractors in the area that there is a need to add humidification. If the house is tight – energy efficient, healthy, and durable, you should not have dry air and certainly should not need more humidity. In fact, living in the home produces humidity and an energy-efficient home traps that humidity inside the home. If there is a problem, it will be high humidity. In fact, if you have dry air, your home is not energy-efficient.
A dehumidifier is a piece of equipment that reduces the level of humidity in the air. Humid air can contribute to mold and mildew issues in your home. It can also lead to condensation on pipes. As a rule of thumb, relative humidity in homes is preferably 30 to 50 percent and can be measured using a humidistat. Installing a dehumidifier as part of your heating and cooling system can improve durability of your home and indoor air quality.
So there is a strong chance that you will need a dehumidifier in your home rather than adding humidity.
The heating and cooling system can be installed independent of a dehumidifier system, but works best when they are combined.
by Charles Hendricks | Jan 15, 2014 | architecture, green term defined, Indoor Air Quality
Anyone that has spent anytime in a vented crawl space in our area can tell you – it is not pleasant. Frozen pipes, dirty air, mold, animals are all possible problems. The idea of a vented crawl space is during the humid summer, the small vents around the foundation will allow enough air flow to dry the crawl space. The humidity in the space comes from the dirt floor, outside air, and even from the house itself. If there are enough vents, if the wind is blowing in the right direction, and if it is not too humid outside – it might stay dry. I have seen dry crawl spaces, but they are rare.
An encapsulated crawl space is the way to fix the moisture issues and protect your indoor air quality in your home. An encapsulated crawl space is a sealed space that has a vapor barrier on the walls and floor. There are no vents and the space should have positive air pressure in the space.
An encapsulated crawl space will help reduce the chance of radon and mold in your home. It provides a better thermal performance reducing your energy consumption. It will contribute to a longer lasting more durable structural system for your home. It will help prevent cold floors. It reduces the chance that you will have mold growing in your HVAC duct work. Also, it reduces the probability of critters living in your crawl space.
There are many benefits to an encapsulated crawl – check out this blog by our friends at Energy Vanguard for their views on the subject.
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by Charles Hendricks | Jan 7, 2014 | architecture, Building Science, Indoor Air Quality
Following up on the blog question posted yesterday. This is a photo taken between a vented attic and a conditioned space. The dirty line at the bottom of the insulation shows the path of air infiltration from conditioned to unconditioned space. This is a typical problem in buildings that do not have proper air sealing. Fiberglass insulation works well as an insulator but does not stop air movement. The insulation becomes an air filter without an air barrier. Air movement also brings vapor movement. Once the insulation gets wet it loses all effectiveness. There is also a chance that the moisture movement will be enough to support mold growth. If you find that your insulation is acting as an air filter and not insulating – making the space air tight will solve the air quality and energy-efficiency issue.
More information on Air Sealing, click here, here, and here.
