Basic properties of fiberglass as an insulator, its types and technical characteristics. Installation of fiberglass insulation and safety measurements.
Fiberglass is a special type of fiber composed of glass. It has a wide range of application areas, and is mainly employed as an insulator in residential and commercial buildings. Fiberglass insulation inhibits spread of cold, heat and sound in houses, structures and cars. By trapping air flow, it keeps premises warm in cold season and cool during summer, and thus serves as a proper method to enhance home energy efficiency.
Fiberglass is a good option for home insulation due to its nonflammable properties. Some estimates have shown that fiberglass conserves about 12 times as much energy as it is spent on its production, and this material can decrease residential energy losses by roughly 40%.
What is fiberglass insulation technology?
In residential houses, fiberglass insulation is usually installed in different structural areas of the building envelope. It comes in any color, depending on manufacturer, and feels like a sponge. You can usually find it in the form of a blanket, which is called batts. Fiberglass is available today in bags having standard length and width. They are usually stapled to the frame wall studs or between the rafts. There are also bags of loose fill which are typically blown into floor and wall cavities of the attic. Most of fiberglass batts are produced with a foil or paper covering that is directed inside the room.
Correctly installed insulation creates a solid membrane that prevents penetration of moisture and disables the fiber particles’ entering the room space. There is different thickness of the batts available; though, the thicker batts you’ve got, the higher heat flow resistance is obtained.
Insulation with rigid fiber boards
Insulation with fibrous boards presupposes application of fiberglass material and is mainly used for upgrading air ducts. It is also appropriate for insulation of house walls, ceiling, attic and basement as fiberglass is capable to sustain high temperatures. The thickness of the product ranges from 1 to 2.5 in providing R-value of nearly R-4. Unfaced boards may further be trimmed with canvas, weatherproof mastic or reinforced insulating cement. Faced boards are mounted similarly. To seal the joints between adjacent boards, you can use pressure-sensitive tape, glass fabric of mastic.
Batt and roll fiberglass for blanket insulation
Fiberglass type of blanket insulation is commonly offered in batts or rolls. They’re composed of flexible glass fibers. Batts and rolls are made in widths that suits to standard gap between wall studs, attic and floor joists and roof rafters. Lengthy rolls are hand-cut and fitted to the insulated surface. They are also produced with facing and without it. Some kinds of product are faced with vinyl, kraft paper or foil-kraft paper that acts as a vapor barrier and sometimes an air barrier.
Batts faced with inflammable material come in various widths and are usually applied for basement walls and other enclosed places where fiberglass insulation is left exposed. Facing makes process of fastening the material much easier. Nevertheless, application o unfaced batts is a more suitable option if you’re going to add insulation atop existing insulation.
Precaution for working with fiberglass
When dealing with fiberglass, an essential thing is to obey certain safety precautions. Otherwise, you’ll need to handle negative affect that fiberglass causes to skin, eyes and respiratory system. Fiberglass is nothing else but tiny glass needles, which with friction permeate into skin and cause allergy, itching and irritation.
First of all, consider what to wear when you work with the product. Always use a filter mask (or respirator with filter), goggles and put on workwear and gloves. In the case you have been in direct contact with fiberglass particles, it is necessary to remove fiberglass insulation from skin right away. There are a few ways to do it, but none of them is 100% efficient in every particular case, so try them one by one till you get a positive effect.
- Rinse your skin with cold water; in two minutes do the same thing using hot water. Thus, the pores will close at first stopping glass fibers from trapping deeper into your skin, and then will open letting the fibers out. This step is a better option for mild cases to stop itching which have happened recently.
- Application of Epsom salts can help draw the glass fibers out of skin. Just add 1 glass of Epsom salt to boiling water. When the salt totally dissolves, pour the solution into the warm bath. Hold the affected spots of your skin in salty water for half an hour. Then, rinse them carefully in cool water to finally remove the rest of fibers.
- Stay in a steamy bath for some time to get your pores open. In a few minutes, gently scrape the nylon cloth (e.g. stockings) across the affected skin. It is a good way to pull the glass particles out of skin. This step is suitable for severe cases.
- Another way is to use the scotch tape. But do not press it too much in order not to push the fibers deeper into your skin. Then quickly rip the scotch tape off the skin.
Warning. Do not scratch or press your skin to get rid of the fibers: this can drive the particles deeper in.
How to install fiberglass insulation
Fiber glass is easy to handle and few tools are needed for its installation.
Before start the insulation work:
- check if you’ve got the proper R-value product that meets the code requirements,
- find out whether you need to install a vapor barrier,
- make sure you’ve got all the needed supplies and products to accomplish the job.
Check up the walls before installation and make sure all the cavities where you’re going to mount the insulation material will have six sides after wall finishing is done. It means as a result you will have exterior sheathing, wooden studs on each side and the wall trim on the interior. Loose-fill insulation and batts laid onto the attic floor and installed under floors aren’t subject to air flow, so they may not be covered on the external side.
Useful article: How to install insulation in attic.
Provide the Air Barrier System
An important issue is to provide an effective system of air barrier in place. You need to seal all paths of air between the ceiling, floor or walls and the outside. This regards to electrical boxes, plumbing and holes for wires. Weather-resistant barriers are taped, caulked or sealed with rigid materials or sprayed on. Having sealed the interior trim with a second air barrier, you may improve the air-tightness of your house.
Best Methods for Batt Installation
For the optimal performance when applying fiber glass batts, it is essential to keep in mind recommendations on how to cut fiberglass insulation. To properly fit the cavities intended for fiber glass installation, cut every single batt so that it is ? in longer than the space between the studs. For custom cavity width the batt is cut wider by ? in. Standard pre-cut batts are ? in wider than a standard cavity and are usually of 16 or 24 inches on center framing. Use care to fit the batt carefully placing it from top to bottom, front to back and side by side. To let the wires through the batt, carve it around the wires and make cuts in the batt to fit it around obstacles like pipes, ducts or electrical boxes.
To obtain optimal operation of batts, it is desirable to properly carry out fastening of batts or rolls, having previously got rid of voids and gaps. Nevertheless, air is a great insulator; fiberglass insulation reduces energy loss by preventing air flow and heat transfer. That is why presence of small gaps containing air provides a certain insulating value.