Project Spotlight: ‘The Camp’ High Performance and Healthy Home Highlights and Lessons Learned

Southern Orientation:

The house sits on a small, rectangular lot that luckily faces south.  This allowed the long side of the house to face south, maximizing winter sunlight into the home.

We placed all of the living spaces and bedrooms along the south wall and added ample windows in those rooms to bring in the lovely, southern light.

 The house is surrounded by very tall pine trees and a neighbor’s house that’s only 60’ away.

The tall pine trees meant that the house wouldn’t be suitable for rooftop solar, so the owner’s aren’t able to generate their own electricity.

The good news is that the wintertime sunlight is able to sneak through the trees and brighten up the house all winter long.  And the trees act as a visual buffer to the house next door.

Window Location and Views:

You have good luck when the view you're trying to capture on your property happens to be facing south.

Many times, the views we want to see out our windows are either east, west or north, which are not the ideal locations of windows if we want to capitalize on south-facing light and warmth.

At 'The Camp', the view to the water is facing east.  And the view from the south is looking directly at the neighbor's house.  

So the challenge was to have enough south-facing windows to benefit from sufficient natural daylight and winter solar warmth while also screening the neighbor's house, and opening up views to the lake on the east side of the house.

We accomplished this by having just enough south-facing windows to let in enough light, but spaced out the windows so that they didn't become a focal point in the rooms.  For example, in the living room the south-facing windows are about 2.5' wide, but they are spaced about 5' apart.  And the real focal point is the east-facing windows toward the lake.

Rectangular Shape:

The shape of the house was deliberate so we could maximize the amount of area that’s facing south.  And we minimized the amount of jogs to keep it as close to a simple rectangle as possible.  (You’ll see when I talk about air sealing that the few jogs we did have caused some trouble in building the high performance building envelope.)  

Big Overhangs:

To maximize natural light and solar heat gain in the winter, we want most of our windows to be located on the south side of the house.  But in the summertime, those windows need to be shaded so the house doesn’t overheat.

The best way to do that is with roof overhangs.  In this house, we extended the roof out 2’ to 2.5’ past the exterior walls of the house.  This allows the windows to be shaded in the summertime but clear to let the sun in during the cold winter months.  

The photo above shows the sun hitting the windows in late November, when we want the warm sun to enter the house.

Cross Ventilation:

The rectangular floor plan also provided a good opportunity for cross ventilation.  This is a great way to naturally cool the house on warmer days.  

The trick is to place windows on opposite sides of the house or of a room, open them up and allow the breeze to travel through the house.  By having the windows on opposite sides of the space, the air is basically being sucked through the house.  So even on non breezy days you’ll notice air moving through your house if you use the cross ventilation technique. And it’s amazing what a little bit of air movement can do to cool you down on warm days. 

In this house, the first floor has an open plan so we put a few windows on the north wall in the kitchen and in the stairway to create the opportunity. (The stairway is a great place for windows because it encourages the hot air to move up and out of the house).  And each bedroom is located on the corner of the house so we could add windows to two sides of each room.

Double Stud Walls:

We really wanted to bump up the insulation in this house to make sure it stays at a comfortable temperature without relying on heating and cooling systems.  

One way to add lots of insulation in the walls is to build a double stud wall system.  It’s a great method because it doesn’t add much complexity to the wall construction, so any contractor should feel comfortable building it.  

The method is to build two 2x4 walls side by side with a small space between them.  (See picture for example).  So rather than having a 5.5” inch cavity that you have in a normal 2x6 framed wall, you have 11” of cavity space that can be completely filled with insulation.  This doubles the amount of insulation you can put in your walls.

This house ended up with R-36 wall insulation (code minimum is R-20 in this climate zone), R-60 roof insulation (code min. is R-49) and R-24 foundation insulation (code min. is R10).

Another cool benefit of double stud walls is that you have a very deep window sill, which is fun. 🙂

Air Sealing:

A house needs to be super air tight if it’s going to be energy efficient and keep you comfortable and healthy.  And this house is no exception.  It was wrapped in an air tight weather barrier with all seams and window openings taped and totally sealed up.

Lesson learned: The air sealing ended up being pretty tricky in the areas of the house where the walls jog out at the library and living room.  The contractor ended up bringing in an additional method of air sealing called Aerobarrier to fill in the gaps that he couldn’t get to with tape and sealant.  

The takeaway is that anytime you have a jog in the floor plan, or you have a dormer or different roof configurations, sealing the house becomes much more difficult.  So the simpler you can make the house design, the easier it will be to air seal and insulate (and keep safe from water intrusion).

Triple Glazed tilt-and-turn windows:

The windows are high performance tilt and turn windows.  This window style opens in two ways.  You can swing it completely open like a door and you can tilt it from the top.  The major advantage to this type of window is that it has a really tight seal when it’s closed.  This keeps air from sneaking in through the window.

The windows are also triple glazed, meaning they have 3 panes of glass.  The benefit of triple pane windows is that it allows the interior pane of the window to be the same temperature as the air in the house.  

Most windows (windows that are single and double paned) are noticeably colder in the wintertime than the air inside the house.  If it’s cold out, you might choose to not sit near the window because you’ll feel the cold coming from it.  This doesn’t happen with triple glazed windows, so your whole house ends up feeling more comfortable.  

FYI: Triple glazed windows are a big benefit in cold climates in locations where you will be near the windows, but they aren't necessary in all climates and locations.

All-Electric Systems:

It was important to the homeowners for the house to not run on any fossil fuels, both for the health of the planet and for their health (which I'll get into more in the next post).  

All systems in the house are run on electricity.

Air source heat pumps:

ASHPs or (mini-splits) are used to heat and cool the house.  There are 4 indoor wall hung units in different areas of the house and those units are tied to 1 outdoor unit that sits in the back out of view.  With such an air tight and well insulated house, you don’t need much heating and cooling to stay comfortable.  

HRV : 

An HRV is a Heat Recovery Ventilator.  This is a type of balanced mechanical ventilation system, bringing fresh air into the house at the same rate that it removes stale, toxic air.  The fresh air travels through small ducts within the walls of the house and distributes fresh air to all living spaces.  

Heat pump water heater:

Heat pump water heaters are pretty cool.  They heat up your domestic water by pulling heat out of the air around it.  This makes them very energy efficient.

There are a couple drawbacks to them though.  They can be a bit noisy and they make the air around them colder because they are taking the heat out of the air to heat up the water.

This project wasn’t actually supposed to have a heat pump water heater because of these two concerns.  Since the house has no basement, the utility room is on the first floor.  That puts the noisy and cold heat pump water heater on the first floor near the living spaces. This was a mistake made by the plumber and wasn’t caught by the general contractor.  The owner accepted the mistake and is ok with the installation, but she does notice the cooler air and noise in that part of the house.

Induction cooktop:  

Induction cooktops are amazing.  They’re electric, but are very different from traditional electric cooktops.  They're very efficient, and they’re a wonderful replacement to gas cooktops.    

No wood stove or fireplace:

We intentionally did not include a woodstove or fireplace in this house (which is a rare thing to see in New England).  Not only are woodstoves and fireplaces bad for the indoor air quality, they also make it much harder to have an air tight house. 

So I always recommend forgoing an indoor wood stove or fireplace and putting one outside the house where you can see it from indoors.

No solar:

Because the house is in a very woodsy setting with tall pine trees to the south, it wasn’t possible to install solar panels on the roof for electric generation.  When this happens, it’s good to look into community solar projects or credits to see if there’s a way to benefit from renewable energy in another way.