6 Things to Consider When Building a Basement
Building a basement with Fox Blocks ICF walls provides durability, integrity, and insulation for below-grade walls. The thermal resistance of ICF also ensures a comfortable and healthy indoor environmental quality. In addition, ICF basements provide resiliency for natural disasters like tornados and floods. They are fast and straightforward to construct, which saves both time and money.
Millennials Want Multi-Use Finished Basements
When looking for a house, the majority of millennials - 73 percent - want the additional space of a habitable finished basement that can accommodate a home office, gym, media room, or even a rentable basement apartment. Therefore the design must create a warm, comfortable, and healthy space. Like all foundations, the basement must support and anchor the entire house and effectively transfer all the load from the house to the ground.
Building Codes are requiring above and below grade walls to have continuous insulation (CI). This means typically poured concrete or CMU foundation walls must have insulation and a vapor barrier installed, adding more labor and materials costs to basements.
In North America, 98 percent of basements constructed use a concrete wall system, like insulated concrete forms (ICFs) and poured concrete.
Things to Consider When Building a Basement
Before deciding which product to use for your new basement, consider these six important characteristics that are associated with basement construction and design.
When building a basement, builders should select products, like ICF walls that will keep the space comfortable in both winter and summer. Basement walls constructed with ICF exceed energy code requirements by reducing energy use by between 20 and 50 percent over other basement wall options, like poured concrete.
- ICF walls contain high thermal mass, provide a continuous air barrier, and have an R-value higher than 22 - much higher than the R-value of poured concrete walls with less than an R3 and must be strapped and insulated to meet code.
- ICF basement walls save money by using significantly less energy, which lowers the monthly heating and cooling bills. ICF walls also allow for smaller downsized HVAC equipment, which reduces new construction costs.
- ICF walls do not require strapping, additional insulation or a vapor barrier.
2. Disaster Resistance
Disaster-resistant basements can lessen the impact of increasingly severe weather events and wildfires. Disaster-resistant design also reduces the ecological and financial cost of rebuilding and repairing.
- ICF wall systems are an ideal product for building disaster-resistant basement walls. The structural integrity and fire-resistance of ICF protects the home and family from tornadoes, hurricanes, wildfires, and other extreme weather events.
- ICF walls are reinforced concrete which can be designed to provide a safe room in the home.
3. Leak-Resistant Walls
For the home’s durability and the health of its occupants, basement walls must not allow water to infiltrate, which can cause mold and rot. Mold can pose serious health concerns, and rot can degrade the integrity of the home. Moreover, preventing moisture reduces a homeowner's long-term maintenance and repair expenses.
- ICF Walls, along with a basement waterproofing membrane and a reliable drainage system, significantly reduce the possibility of moisture intrusion. ICF foundations also provide double the compressive strength (resistance to shrinking) of conventionally poured concrete foundations; therefore, ICF has less chance of moisture intrusion than poured concrete.
Moisture Problems with Poured Concrete Basements
Several problems may happen during the construction of a poured concrete basement that make the walls prone to water infiltration.
- Regular poured concrete can crack and leak if not prepared correctly.
- Moisture can leak through non-structural cracks in the poured concrete basement walls, like at the top of the walls, where the floor and wall meet, or through the porous concrete.
- Leaks may occur if the basement wall settles, drops, or sinks due to the soil below the basement foundation collapsing.
- Wood strapping on basement walls is organic materials that may be subject to mold and rot from condensation and/or moisture intrusion.
4. Good Acoustics
Building a basement with excellent acoustics optimizes the space for a media room, apartment, or home office. The design of a soundproof basement must consider the ceiling, walls, and floors:
- ICF offers an excellent basement wall product for achieving good acoustics. Most ten- or 11-inch ICF walls, with a six-inch concrete core, advertise STC ratings of 50 to 55. A Sound Transmission Class (STC) rating represents in decibels how much sound travels from one side of the wall to the other.
5. Wall Space
Most residential basements require 8" poured concrete walls or 8" to 10" CMU walls. Generally, an ICF as reinforced concrete may be designed with a 6" concrete core.
To meet certain building codes requirements for basements 2x6 strapping is required over the 8" poured concrete walls, expanding the wall thickness and reducing interior space.
ICFs have built-in fastening strips that allow the gypsum board to be applied directly to the ICF.
6. Why You Should Consider Fox Blocks ICF for Your Next Basement Building Project
Fox Blocks ICFs provide an all-in-one wall assembly for fast and low-risk basement construction by combining five building steps into one; insulation, air barrier, vapor retarder, structure, and attachment. The all-in-one wall system lessens the need to coordinate multiple trades, which saves money and significantly hastens project delivery. Fox Blocks ICFs create energy-efficient, disaster-resistant, and durable basements with excellent IEQ:
- High thermal mass provides continuous insulation for energy-efficient basement walls. Fox Blocks' basement walls exceed ASHRAE/ANSI 90.1 energy code requirements with an R-value of 23.
- Disaster-resistant ICFs can protect a family from severe wind events and fires.
- Steel-reinforced concrete can withstand tornado and hurricane winds exceeding 200 mph and projectile debris moving over 100 mph.
- Fire-resistant, with a fire-resistance rating (ASTM E119) of 4 hours for the 6-inch blocks and 2 hours for the 4-inch blocks.
- They produce durable and healthy basement walls. The wall assembly includes a vapor retarder that contributes towards a moisture-resistant basement wall. However, for below-grade walls, the Fox Blocks system needs a dependable drainage system and waterproofing membrane to ensure moisture-resistance.
- Promotes a healthy basement because they contain little to no VOC.
- Contributes towards a durable basement because they lack organic materials - something termites like to eat. However, Fox Blocks recommends Polyguard Products, Inc. 650 XTM or 650 XTP membranes, to ensure protection against termites
- Provides high sound reduction. The Fox Blocks Series achieves a high ASTM E90 Sound Transmission Classification (STC) rating of greater than 50.
Fox Blocks, a division of Airlite Plastics Company, is available across North America. Find a local distributor on our website.