One of the most effective ways to reduce your electricity bill is to insulate your mobile home’s attic. According to the US Department of Energy, properly insulating this area can help you save up to 50% on your heating cost.
But before you embark on a DIY insulation project, there are some things you need to perform:
- Check your local building code’s R-value requirements.
- Measure between joists to find the correct width for your attic’s insulation.
- Make sure that you seal gaps, especially areas around the ductwork, wires, and plumbing.
Installing Attic Insulation with Roll or Batt
Here is a step-by-step instruction on how to install roll or batt insulation for your attic:
1. Choose your insulation material
For attic insulation, the most commonly used materials are cellulose, fiberglass, and rock wool.
- Cellulose. This is made of recycled, tightly packed paper treated for fire and airflow resistance.
- Fiberglass. This is arguably the most commonly used material for attic insulation because of its affordability and easy installation.
- Rock wool. Also called mineral or slag wool, this material is created by spinning fibers from molten textile.
2. Choose your type of insulation
There are two types of attic insulation you can choose from–loose fill or batt/roll.
Loose fill, also called blown-in insulation, is ideal for tight spaces and patchwork–i.e., topping off existing attic insulation. Meanwhile, you’ll need a special machine when working with this material.
On the other hand, batt and roll insulation, also referred to as blanket, is more commonly used for DIY projects because they work well in open spaces like attic and fit easily between joists and wall stud cavities.
3. Choose a material with a high R-value
Each insulation material is rated by an R-value, which determines the level of resistance to heat flow. The colder the climate, the higher the R-value you need to prevent heat loss during the winter.
Keep in mind that colder climates require insulation materials with an R-value of at least 49.
4. Calculate how much insulation you need
For an attic, a good rule of thumb is to install two layers of insulation and cover the wood joists to promote good ventilation.
The first layer sits between the joists and faces against the drywall, while the second one runs perpendicular to it and faces the “unconditioned” space, so the moisture does not collect between the layers.
You can determine the amount of insulation you need by multiplying the attic’s length by its width.
5. Prep the space
Remove any existing insulation that looks worn out, dingy, or compressed. If you have mold/mildew growth or roof damage, you must address these problems before installing your new insulation.
(Note: Roof damage and mildew growth are best left for licensed contractors.)
6. Pay close attention to the pipes and vents
If your home has water pipes running in the attic, make sure that they are wrapped with foam pipe sleeves to prevent moisture buildup. You can easily slide these protective sleeves over the plumbing and cut any excess with a utility knife.
Also, keep in mind that bath fans should not vent into an attic because it can lead to excess moisture, and ultimately, mold and mildew growth.
7. Close gaps and crevices
Seal gaps and crevices to prevent heat loss around fixtures. To do this, you can caulk around smaller spaces like electrical boxes and spray foam around light fixtures and pipes.
8. Caulk the heater flue
Caulk around the flue using a fire-resistant material and cover it with two pieces of sheet metal to prevent fire hazard.
A good rule of thumb is to keep the insulation at least 3 inches away from heat-generating fixtures like heater flues, chimneys, exhaust fans, and recessed lights. To further eliminate fire hazard, install metal sheets around these fixtures.
9. Inspect the recessed light fixtures
If your recessed lights come with a Type-IC label, it means that they don’t pose a fire hazard if they come into contact with insulation material. But if they don’t have this label, you need to keep your insulation away from them.
10. Check the attic’s airflow
To allow airflow and prevent moisture buildup, install rafter vents at the soffit, which you can slide along the underside of the roof and attach with staples. Meanwhile, the insulation should sit against the vents.
11. Map out your utilities
You need to map out your utilities before covering them with insulation. Additionally, mark wiring fixtures on the rafters above.
12. Insulate the joists
If your home does not have a layer of insulation between the joists, you need to install it before adding a layer over them. Ensure that the roll between the joists is facing against the drywall and is tucked snugly between the spaces where the ceiling joists meet the rafters.
If you’re working with fiberglass insulation, make sure that you don’t compress its rolls to maintain its energy efficiency.
13. Install the second layer of insulation
Install the second layer by tucking small pieces of insulation between the rafters and vents. Make sure that it is facing the “unconditioned” space.
Meanwhile, you can leave any existing insulation as long as it does not look damaged or compressed.
14. Insulate the hatch
One of the easiest ways to insulate the hatch is to use a self-adhesive weatherstripping where the door comes into contact with the frame. Just make sure that you apply the adhesive to the back of the hatch and then press a foam against it.