Old House Insulation

Many houses built from the 1900s to the 1950s still stand the test of time because of the sturdy materials they were built with. They were usually built out of wooden posts and beams. Even though it may not seem like it, wood is amazingly resilient when it comes to moisture. When given enough time to dry, wood can get wet over and over without any damage. The greatest drawback of old houses can easily be seen whenever a new utility bill arrives in your mailbox. Old houses have very little in terms of proper insulation, and the insulation they have is inferior to newer insulation materials. There were no building or ventilation standards, and that means the roof, attic, and wall insulation is sparse or in some cases non-existent. New types of insulation that come in rolls, a prime example being prodex total 10M, combine a variety of insulation materials that all work together in providing the best insulation for your old home and will help in reducing the huge numbers in your utility bills.

What Do You Do with Existing Insulation?

Insulation in old houses usually consisted of a number of everyday materials such as wood shavings, corn cobs, newspaper, and even seaweed. Some types of insulation that were used as early as 1875, like mineral wools (substances like rock slag “spun” into fibers) are still used today. These materials can be left in place.

Insulation materials that were introduced in the mid-20th century that create the most cause for concern are the types that contain asbestos and urea-formaldehyde.

By the 1930s, asbestos was a common material in insulation products. Insulation that contains asbestos can be a cause for concern because asbestos is a known carcinogen. If you suspect having asbestos in your old house, you should have the insulation material tested. Asbestos is particularly dangerous when it is airborne. That means complete removal of the insulation might be too invasive and should be left alone if it isn’t flaking. If your project demands tearing down all the walls, you can get rid of the asbestos insulation, but make sure you encapsulate it to prevent it from flaking and creating asbestos dust.

A combination of resin, hardener, and compressed air is called urea-formaldehyde and was developed as an insulation material in the 1970s. It was installed by being foamed in between walls. It was discontinued in the 1980s when concerns of off-gassing as the product breaks down arose. After the initial curing, the material will not off-gas further until it comes into contact with water or moisture. You can have your home tested for these vapors by a local environmental company.

Before spray foam can be placed, anything in your attic, crawl space or rim joist must be removed. For now, if there is fiberglass in the walls it may remain in place without interfering with the injection foam installation. There are also circumstances when the external walls contain blown-in cellulose that must be removed. If this is the case, have a professional suck up as much of the material as possible.

If the typical insulation in these locations becomes wet, it must be removed to avoid mold and mildew growth. As the mold spreads, you may notice that it seems damp and may have black patches throughout. The removal of all of that old insulation also removes all of the dust and allergens that were contained inside those materials.

Cellulose and fiberglass will move, settle, and sag with time. If that's the case, you may add extra insulation, but you'll need to rake the cellulose and make sure the fiberglass is correctly cut and fitted.

When it comes to your home's walls, you may add extra insulation while keeping the original intact. Blown-in materials may be used to install insulation without breaking down your walls. Foam insulation is the greatest blown-in solution in terms of creating a comfortable and energy-efficient air barrier. 

Is It Worth Insulating an Old House?

First, establish whether or not you have insulation. It's simple to tell if you have attic insulation, which is generally loose fill between ceiling joists or exposed batts of colored fiberglass. You may also look for a succession of patched holes on your outside walls. This is an indication of blown-in insulation.

Old houses may be drafty, and warm air can seep in from a variety of sources. Examine your home to identify where you could be losing heat. Chimneys and fireplaces without functioning dampers are common. Cracks around windows, ducting, electrical outlets, and recessed lighting are areas to consider.

It should be noted that the principal source of heat loss is the roof of the home. Heat rises and can escape via inadequately insulated roofs. A good and quick solution for better insulation is installing 24 inch prodex Total 5M in your attic or underneath your roof. This applies to both old and new houses.

You may not even need new insulation in the walls, attic, and roof of an old house. There are more ways to control temperature aside from covering leaks and adding insulation. Making sure your heating and ventilation system is functioning properly is essential. On frigid winter evenings, aging, inefficient furnaces may be unable to meet the heating demands of large, historic homes. Consider hiring an HVAC professional to switch to a more energy-efficient model.

Another suggestion is to seal and insulate heating/cooling ducts, particularly those that run through colder areas such as attics, basements, and unheated garages. Seal seams and joints with mastic sealant or foil tape, then wrap them with duct insulation.

Interior Wall Insulation in an Old House

The walls of an old house might complicate the installation procedure, but it's nothing that a qualified contractor couldn't manage.

Almost all older homes have double and triple studs. As a result, when contractors remove the siding and drill into the house. The double and triple studs just require more drilling time for the employees to ensure the task is completed correctly. Another thing crews discover in older homes is an abundance of nails. They employ an auger-style bit that grinds out the wood, and when it strikes a nail, it stops. When crews are aware that they will be working on an older home, they bring extra drills. In some circumstances going for hybrid acoustic wall insulation in interior walls can add to your overall insulation, while also giving you the added benefit of acoustic insulation between the rooms of your old house.

Aside from the elements we just covered, the method of insulating the outside walls of an older home or a modern existing property is essentially the same.

The kind of siding on your home might affect the installation procedure, from the technique employed to the time required to finish the task. We deal with vinyl, aluminum, brick, wood, slate tiles, and stucco, among other materials. The injection foam insulation may be put in your external walls from the outside, without the need to remove any drywall.

Insulating the Attic and Roof

Increasing attic insulation is the single most beneficial energy modification that most homes can do. It doesn't matter if you use bubble wrap insulation or loose-fill insulation as long as you get enough insulation up there.

This is easy and not specific to older homes, but it is also the simplest and least expensive energy enhancement you can do. In theory, there is no practical upper limit for attic insulation depth. For example, a minimum of around 20" of batts or loose-fill insulation in the attic makes sense in colder areas. It's much better if you can accommodate 25" or 30" of depth beneath your roof. That means that prodex total 5M plus or prodex total 5M is a great all-in-one solution for most attics and roofs. Many older homes require greater attic ventilation in addition to inadequate attic insulation.

Ridge vents are more effective than mushroom-style roof vents and look much better, especially on older homes. It's also extremely simple to add ridge vents to an existing roof, even if you're not replacing all of the tiles.

How to Insulate Walls in an Old House

Many homeowners have made the error of drilling holes in their walls, blowing in cellulose insulation, and then carefully closing the walls up again. Condensation may build inside the walls as a result of this procedure. Moisture can accumulate, eventually causing mold, wood rot, and hazy glass. If you’ve checked with a contractor and have made sure that you need wall insulation in your old house, knowing how to properly insulate it is important.

Focusing on the facade of a historic house is one technique to insulate its walls:

  • Apply a vapor barrier/house wrap to the outer walls.
  • Insulate using a 1-inch foam board.
  • Cover the insulation with siding.
  • Replace aging windows with energy-saving models.
  • Caulk window trims and install weatherstripping to decrease air leaks.

If you've done everything else and are determined to insulate the walls of an old house, consider the following precautions:

  • Before drilling holes, remove the weather protection and cladding.
  • Replace single-pane windows with double-pane windows.
  • Water-resistant flashing should be replaced or added.
  • Fill drill holes with loose spray foam insulation and seal them.
  • Continue with the previous stages for external wall insulation.

What is the Best Type of Insulation

Insulation for buildings is usually classified into four general types:

  • Loose fill (cellulose, mineral, or glass fibers);
  • Batts (fiberglass, cotton, or various wools);
  • Rigid insulation boards (composed of plastic foams or glass fibers);
  • Expanding sprays (proprietary systems).

Batt and rigid insulation usually come into play during a major restoration which requires tearing down the walls and building new ones or if you’re insulating unfinished spaces such as attics. Loose fill is the most common type for a quick boost to your old house insulation because it can reach many places that rigid and batt insulation simply can't. Loose fill is generally considered as the greenest solution among all other types of insulation because it’s mostly made from recycled newspaper. Blown-in insulation does a good job of insulating hard-to-reach places like the space in between the walls, crawl spaces, or attics. Blown-in insulation is usually made from expanding foam and is very efficient at insulation considering how light it is compared to the other types of insulation.

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