Common concerns: Outdoor spaces

As a home inspector, I see common concerns in houses and listings. I will discuss these concerns over my next few blog posts but start with a big one – outdoor spaces. One of the biggest, and potentially most damaging, concerns relates to potential water ingress into the building structure. Most houses are constructed of a wood framework with wind and water barriers on the outside, insulation in the middle wall cavities, and then an internal finish layer of drywall or plaster. The wood framework and internal layer are susceptible to rot and mold and need to be kept dry. Moisture is controlled with the wind and water barriers, an air gap, and a durable exterior cladding material to resist driving moisture (such as rain blowing against the side of the building). The cladding material, as well as the water and wind barriers, are water resistant but not waterproof. That means that you want to promote water shedding off the exterior walls and away from foundations. The effectiveness of these efforts is impacted by everything outside of and around the house. Things like trees, gardens, decks, patios and even grass can slow down or increase water within the wall; therefore, increasing the likelihood of water ingress. If you are planning on building a deck or planting a garden for your outdoor space, I am providing some examples here of what not to do!

In this first example, you can see in image 1 that the deck is built around the air conditioner, the gas meter, and the venting for two appliances. Surrounding the air conditioner cuts off the free airflow that carries heat away. This will not only reduce the cooling potential for the house, but it will also overload the air conditioner and shorten its life. When the condenser fails, which is what happens from overloading the unit, a replacement could cost upwards of $7,000; however, would also need to remove the deck to replace the condenser unit. In addition, the piping from the condenser to the house evaporator is installed below the deck.

Image 1: Gas meter and air conditioner buried in deck

In image 2, you can see that the gas meter and the service regulator are at or below the deck surface. This is a code violation. The gas regulator needs to be above the snow line to prevent ice formation in the regulator’s vent that may result in the failure of the regulator. There needs to be 33cm (13”) between the bottom of the regulator and the surface below it. The venting of appliances is required to be above the snow line as well. To the right of the sliding patio door, you can see two white pipes extending halfway up the door. These are the air intake and combustion vent terminations for a direct vent appliance (e.g., furnace). These pipes should be secured and moved away from the doorway where combustion products can enter the house through an open doorway. On the other side of the patio door, you can see the drier vent just below the deck surface. This is also a code violation to vent below a deck because it can lead to a vent fire under a few different scenarios. Here is a link to a CBC article on the dangers of drier vent fires to learn more: Dryer fires a real hazard that can happen at a moment's notice | CBC News

Image 2: Gas vent and inlet pipes not secured and at doorway

Your house has an outer layer or cladding to protect the components in the wall that do not like to be exposed to water, snow, and wind. This outer layer could be bricks, stone, vinyl siding, wood cladding, stucco, or a number of other materials. They are all designed to repel water but they don’t provide 100% waterproof protection. The cladding can’t protect valuable house from a flood or water lying against it; rather, the cladding is installed to allow for water to drain out of the wall construction as well as promoting air circulation to help dry out the internal wall when there is moisture that gets in. This drainage is to protect your interior from rot and mold. Image 3 shows a deck that is installed over the wall cladding that hasn’t been done properly and is now showing signs of moisture damage. To install properly, flashing material would need to be added to redirect the water from the cladding. I can guarantee that this wall construction is also compromised and there is a moisture issue within the house as a direct result of this deck placement. Since it is within the wall construction, it is almost impossible to see until it is too late.

Image 3: Deck against wall cladding causing damage

Similarly, in image 4, the deck looks beautiful but is built over the bottom run of the wall cladding without a flashing material. Looking carefully at the bottom of the cladding on the bay window you can see indications of damage to the cladding at the interface of the patio and the building. Flashing that should be used would be placed under the cladding and laid over the patio to direct surface water away from the wall.

Image 4: Patio over wall covering showing water damage

Another common cause of wall and foundation moisture issues are gardens that are built up around the home. In image 5, you can see that the garden height has been increased and now covers the wall’s weep holes (those spaces you can see in the brick work). Typically, these holes drain water that has gotten into the wall cavity and allow air movement to keep the wall cavity dry. With the weep holes covered, soil moisture and microbes can directly enter the wall structure. This is not what you want. Imagine putting a piece of wood on the ground – how long would it take before it becomes waterlogged and shows signs of rotting? It is necessary to have the soil sloped away from the foundation to divert ground water away and there should be at approximately 8” between the soil and the bottom of the wall covering. Additionally, the trees in this garden are too close to the house leading to moisture damage (as shown by discolouration of the brick) and their roots attacking the foundation walls. Over time, trees planted too close to the house not only contribute to moisture damage, but also keep your foundation and wall cladding from drying out and they can also be fire hazards.

Image 5: Garden covering brick weep holes

The tree in image 6 is another example of growing too close to the house and the chimney termination which is also a fire hazard.

Image 6: Tree too close to home and chimney vent

If you are looking at a home where someone has added gardens, a patio, or a deck, here are some things to look for:

• damage to the wall cladding;

• moisture stains;

• decreased separation of cladding from the soil;

• compromised continuity of the cladding where moisture can enter the wall; and

• construction around exterior components like gas meters, regulators, vents and air conditioners that can be dangerous.

#HomeInspection #OutdoorSpaces #WaterDamage #FireHazards #HomeOwnership