WHAT IS A KNEE WALL?
A knee wall is a vertical wall in the attic that has living space on the other side. Generally, you will see a knee wall in the attic when there is a change in the height of the ceiling in the living space. It will be finished on one side (drywall and paint) that faces the conditioned space while the opposite side is unfinished and faces unconditioned space such as attic or crawl space. If you have a split level or tri level home you likely have a knee wall that separates the two attic elevations. Knee walls can be a source of energy problems because they can be uninsulated or have insulation that falls out. In the summer, uninsulated knee walls can allow heat from the attic to conduct into the conditioned space. We commonly see knee walls that either have no insulation at all or have a thin fiberglass batt which allows conditioned air to exchange from the living space into the attic. When we encounter knee walls we prefer to add closed cell 2-part spray foam because this not only insulates knee walls but also provides an effective air barrier to eliminate heat exchange between the conditioned living space of a home with the unconditioned space of an attic.
A knee wall is a vertical wall in the attic that has living space on the other side. Generally, you will see a knee wall in the attic when there is a change in the height of the ceiling in the living space. It will be finished on one side (drywall and paint) that faces the conditioned space while the opposite side is unfinished and faces unconditioned space such as attic or crawl space. If you have a split level or tri level home you likely have a knee wall that separates the two attic elevations. Knee walls can be a source of energy problems because they can be uninsulated or have insulation that falls out. In the summer, uninsulated knee walls can allow heat from the attic to conduct into the conditioned space. We commonly see knee walls that either have no insulation at all or have a thin fiberglass batt which allows conditioned air to exchange from the living space into the attic. When we encounter knee walls we prefer to add closed cell 2-part spray foam because this not only insulates knee walls but also provides an effective air barrier to eliminate heat exchange between the conditioned living space of a home with the unconditioned space of an attic.
WHAT IS A CANTILEVER?
A cantilevered floor is anywhere on the exterior of your home where you see a “bump out”. It’s a floor that extends beyond the foundation or supporting wall below it. Cantilevers can be used to create bump-outs, bay windows, rooms over porches, or to make upper floors larger than lower floors. Unfortunately, cantilevers can be a common source of heat loss in a home because there is commonly air leakage through cantilevered floors due to gaps or insufficient insulation around the floor assembly, leading to unwanted airflow between the interior and exterior of the home. In order to alleviate the air leakage, installing dense packed insulation is a great solution to this problem.
A cantilevered floor is anywhere on the exterior of your home where you see a “bump out”. It’s a floor that extends beyond the foundation or supporting wall below it. Cantilevers can be used to create bump-outs, bay windows, rooms over porches, or to make upper floors larger than lower floors. Unfortunately, cantilevers can be a common source of heat loss in a home because there is commonly air leakage through cantilevered floors due to gaps or insufficient insulation around the floor assembly, leading to unwanted airflow between the interior and exterior of the home. In order to alleviate the air leakage, installing dense packed insulation is a great solution to this problem.
WHAT IS A RIM JOIST?
A rim joist is the joint where your basement or crawl space walls and ceiling meet. We want to be sure to add a material that not only insulates this area but also provides an air barrier between the living space of your home and the exterior and, for this reason, we apply 2-part spray foam to rim joists because 2-part spray foam is one continuous material that provides the highest insulation value as well as providing an air barrier.
A rim joist is the joint where your basement or crawl space walls and ceiling meet. We want to be sure to add a material that not only insulates this area but also provides an air barrier between the living space of your home and the exterior and, for this reason, we apply 2-part spray foam to rim joists because 2-part spray foam is one continuous material that provides the highest insulation value as well as providing an air barrier.
WHAT IS AN EXTERIOR TOP PLATE?
Exterior top plates are typically the 2 longest walls in the attic where the pitch of the roof is the lowest. It is the area that the ceiling of the attic meets the floor in the triangle shape of a home’s roof. Since this area is such a low clearance area adding loose filled insulation isn’t able to achieve the recommended R60 to prevent heat loss in the attic or provide an air barrier, so we recommend applying 2 part spray foam to maximize the R value in this low clearance area as well as air seal to minimize heat loss and prevent roof ice damming.
Exterior top plates are typically the 2 longest walls in the attic where the pitch of the roof is the lowest. It is the area that the ceiling of the attic meets the floor in the triangle shape of a home’s roof. Since this area is such a low clearance area adding loose filled insulation isn’t able to achieve the recommended R60 to prevent heat loss in the attic or provide an air barrier, so we recommend applying 2 part spray foam to maximize the R value in this low clearance area as well as air seal to minimize heat loss and prevent roof ice damming.
WHAT IS ROOF ICE DAMMING?
Roof ice dams occur when heavy snow buildup melts during the day and then re-freezes during the cold temperatures of the night. After several times of melting-freezing cycles, it’s common for the melted water and ice to work up under the shingles until water enters the attic space and eventually can cause damage to the ceilings and walls of the attic. In order to prevent this melting-freezing cycle it’s important to properly insulate your attic, including the exterior top plates of your attic.
Roof ice dams occur when heavy snow buildup melts during the day and then re-freezes during the cold temperatures of the night. After several times of melting-freezing cycles, it’s common for the melted water and ice to work up under the shingles until water enters the attic space and eventually can cause damage to the ceilings and walls of the attic. In order to prevent this melting-freezing cycle it’s important to properly insulate your attic, including the exterior top plates of your attic.
WHAT IS CONDITIONED SPACE VS UNCONDITIONED SPACE?
The conditioned space of a house is the space that is finished with drywall and is used as living space while the unconditioned space is an area that isn’t finished and isn’t used as living space.
The conditioned space of a house is the space that is finished with drywall and is used as living space while the unconditioned space is an area that isn’t finished and isn’t used as living space.
WHAT IS 2-PART SPRAY FOAM?
Closed cell 2-part spray foam is by far the best insulator on the market today. With an R value of approximately R6 per inch it not only provides a better insulation value but it is also one continuous barrier - so it is also an effective air sealing material. Not only is it a superior insulator and air barrier, it is also water resistant and is composed of materials that don’t provide an environment to promote mold growth. We highly recommend applying 2 part spray foam to areas such as attic exterior top plates and knee walls in addition to crawl space and basement rim joists and walls but we can also apply 2 part foam to the roof deck of an attic to either insulate your attic thoroughly or provide a conditioned space if you’re interested in adding additional rooms to the attic space.
Closed cell 2-part spray foam is by far the best insulator on the market today. With an R value of approximately R6 per inch it not only provides a better insulation value but it is also one continuous barrier - so it is also an effective air sealing material. Not only is it a superior insulator and air barrier, it is also water resistant and is composed of materials that don’t provide an environment to promote mold growth. We highly recommend applying 2 part spray foam to areas such as attic exterior top plates and knee walls in addition to crawl space and basement rim joists and walls but we can also apply 2 part foam to the roof deck of an attic to either insulate your attic thoroughly or provide a conditioned space if you’re interested in adding additional rooms to the attic space.
WHAT IS OFF GAS WITH 2-PART SPRAY FOAM?
2-part spray foam is a material that we technically manufacture at the time of your project through a 2 chemical combination process. During this combination process an off gas is created that’s bad for inhalation and eye exposure so if it’s in a large amount or if it’s being applied in areas that vent up through the home such as crawl spaces or basements we recommend that no one is present during the application process and for up to 24 hours while the spray foam cures. Per 2-part spray foam manufacturer recommendations, at least 4 hours is needed for the off gas to dissipate IF the spray foam is being applied in a well ventilated area. If the area isn’t well ventilated 12-24 hours is the recommendation, so we always recommend to vacate for 24 hours to err on the side of caution. If the application is in the attic which is vented to the exterior your exposure should be minimal if the only areas you are having 2-part spray foam applied is exterior top plates and/or knee walls but if you have a large knee wall area in your home there is a stronger chance of exposure.
2-part spray foam is a material that we technically manufacture at the time of your project through a 2 chemical combination process. During this combination process an off gas is created that’s bad for inhalation and eye exposure so if it’s in a large amount or if it’s being applied in areas that vent up through the home such as crawl spaces or basements we recommend that no one is present during the application process and for up to 24 hours while the spray foam cures. Per 2-part spray foam manufacturer recommendations, at least 4 hours is needed for the off gas to dissipate IF the spray foam is being applied in a well ventilated area. If the area isn’t well ventilated 12-24 hours is the recommendation, so we always recommend to vacate for 24 hours to err on the side of caution. If the application is in the attic which is vented to the exterior your exposure should be minimal if the only areas you are having 2-part spray foam applied is exterior top plates and/or knee walls but if you have a large knee wall area in your home there is a stronger chance of exposure.
WHAT IS THE BUILDING ENVELOPE?
The building envelope refers to the outer shell of a building that separates the interior conditioned space from the external environment. The building envelope helps to protect and regulate the indoor environment. When we insulate and air seal an attic that seals the envelope and puts the attic into the outside of the building envelope. Contrarily, when we encapsulate a crawl space that brings the crawl space into the building envelope to eliminate gasses and moisture from permeating into the base of a home, effectively creating a much healthier environment for the interior of your home.
The building envelope refers to the outer shell of a building that separates the interior conditioned space from the external environment. The building envelope helps to protect and regulate the indoor environment. When we insulate and air seal an attic that seals the envelope and puts the attic into the outside of the building envelope. Contrarily, when we encapsulate a crawl space that brings the crawl space into the building envelope to eliminate gasses and moisture from permeating into the base of a home, effectively creating a much healthier environment for the interior of your home.
WHY AREN’T VENTS NECESSARY IN CRAWL SPACES?
When a crawl space is properly encapsulated crawl space vents are no longer necessary. Originally, builders added vents to crawl spaces to allow fresh air to circulate to cut down on gasses and moisture in crawl spaces but once we add a soil/gas moisture barrier to prevent moisture from coming up into the crawl space from the soil below and air seal rim joists with 2 part foam and also properly insulate crawl space walls we also want to seal off the vents so there aren’t any penetrations to allow cold air and moisture to circulate into the crawl space.
When a crawl space is properly encapsulated crawl space vents are no longer necessary. Originally, builders added vents to crawl spaces to allow fresh air to circulate to cut down on gasses and moisture in crawl spaces but once we add a soil/gas moisture barrier to prevent moisture from coming up into the crawl space from the soil below and air seal rim joists with 2 part foam and also properly insulate crawl space walls we also want to seal off the vents so there aren’t any penetrations to allow cold air and moisture to circulate into the crawl space.
WHAT DOES IT MEAN TO "TENT" WATER PIPES?
When insulating a cavity, such as a cantilever or garage ceiling, the one thing that you have to be cautious about is if there are water pipes. When insulating the garage ceiling, if there is also a bathroom above the garage, this means that there are often times water pipes that run through the garage ceiling and if we're filling a cantilever in an area such as bathroom or kitchen there could also potentially be water pipes in the cavity. It’s very important to ensure that you don’t put insulation between the pipes and the warm floor above – the warm house is what keeps the pipes from freezing and we don’t want to cut the pipes off from that heat source. When there are bathrooms above the garage the best practice is to remove the drywall under the water pipes to evaluate where the water pipes are located in the cavity – if the water pipes are contained in the top half of the cavity we can add insulation in the cavity without the risk of cutting the pipes off from their heat source but if they are contained in the lower half of the cavity we need to create a “tent” to ensure the warm air can still reach the water pipes to prevent pipe freezing and fill the cavity around the “tent”.
When insulating a cavity, such as a cantilever or garage ceiling, the one thing that you have to be cautious about is if there are water pipes. When insulating the garage ceiling, if there is also a bathroom above the garage, this means that there are often times water pipes that run through the garage ceiling and if we're filling a cantilever in an area such as bathroom or kitchen there could also potentially be water pipes in the cavity. It’s very important to ensure that you don’t put insulation between the pipes and the warm floor above – the warm house is what keeps the pipes from freezing and we don’t want to cut the pipes off from that heat source. When there are bathrooms above the garage the best practice is to remove the drywall under the water pipes to evaluate where the water pipes are located in the cavity – if the water pipes are contained in the top half of the cavity we can add insulation in the cavity without the risk of cutting the pipes off from their heat source but if they are contained in the lower half of the cavity we need to create a “tent” to ensure the warm air can still reach the water pipes to prevent pipe freezing and fill the cavity around the “tent”.