DIY Insulation Do’s and Don’ts, Tips to Warm Your Home

A few DIY tips on insu­la­tion mate­rials and things you should and should not do when insu­lating your home.

There are several types of home insu­la­tion and different appli­ca­tions for each. I will cover the different types and uses for each and offer a few tips to help keep your house warmer in the winter and cooler in the summer.

The most popular and widely used type of insu­la­tion is fiber­glass — which is actu­ally made from spun glass. Fiber­glass insu­la­tion is typi­cally used to insu­late floors, walls, ceil­ings and attics. It comes faced (paper backed) and un-faced, in various widths and R-values.

R-value is simply the measure of thermal resis­tance (how much the insu­la­tion slows the transfer of warm air to cold air). So the higher the R-value the more resis­tance the insu­la­tion offers. Learn more about R-value.

There are many other types of insu­la­tion such as;

  • Rigid foam (extruded poly­styrene), used primarily for exte­rior applications.
  • Cellu­lose (made from recy­cled paper), used for insu­lating walls, ceil­ings, attics and floors.
  • Radiant barriers (closed cell foam faced on both sides with foil) use for insu­lating floors, walls, ceil­ings, attics, garage doors, water heaters and metal commer­cial build­ings, and
  • Spray foam (a two-part liquid containing a polymer and a foaming agent) used for insu­lating walls, ceil­ings and other inte­rior closed spaces.

These prod­ucts all have different R-values, mate­rial cost and instal­la­tion cost.

Do it Your­self Insu­lating Do’s and Don’ts.

  • Do not crush or stuff fiber­glass insu­la­tion into a space. Crushing the insu­la­tion reduces the effec­tive­ness of the product. More in a space is not better.
  • Do wear a mask and protec­tive clothing when working with fiber­glass insu­la­tion. Who wants to breath spun glass into their lungs.
  • Do not block soffit and gable vents when initially insu­lating or adding insu­la­tion to your attic. Good air flow is crit­ical to preventing conden­sa­tion. Condensation/moisture will ruin most insu­la­tion and create an envi­ron­ment for mold to take hold.
  • Do install a mois­ture barrier (plastic/polyethylene) over your insu­lated walls and seal (tape) all seams as well as the top and bottom of the walls. This will help insure that there is less transfer of warm air to the cold air, thus virtu­ally elim­i­nating condensation.
  • Do not dispose of any insu­la­tion by burning. Burning insu­la­tion is toxic, harmful to you and the envi­ron­ment. You can easily dispose of the extra or old insu­la­tion by placing it in plastic bags and taking it to your local refuse disposal station (dump).
  • Do use radiant barriers to insu­late the inside of your garage door and around your water heater. This is a great way to save energy and it is quite inex­pen­sive. Radiant barriers are less expen­sive than rigid insu­la­tion, are far more effec­tive and easier to use. Radiant barriers are also fantastic for use as a mois­ture barrier/underlayment for lami­nate floors over concrete. Since the radiant barrier acts as a thermal break the cold and mois­ture can not move from the concrete up through the flooring. It also adds just a bit of cushion to the floor for comfort, (as it is only 1/4″ thick).

Follow these do-it-yourself insu­la­tion tips and you will truly succeed with speed.

If you have ques­tions about your DIY projects, just ask your personal DIY consul­tant. I’m here to help you.

Thanks again,

Your DIY Answer Guy.
For more DIY tips, follow me on twitter here

DIY Help Category Heating & Air
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We put fiberglass insulation in our crawl space (shares a wall with a bedroom) and then covered it with plastic to protect it from the elements (water, animals), but we were then told that the insulation needs more ventilation. Do we need to remove the plastic or perhaps cut slits in it to ventilate? Thanks for your help!


Hey Lary, I am insulating my basement with R-15 with paper backing... I was wondering when I install the insulation in the ceilings where the boiler pipes are, will the paper catch fire if it is laying on the pipe?


Thinking of using Prodex for my basement concrete floor.

How critical is it to install a plywood sub-floor on top of the Prodex prior to installing laminate wood floors?



How do you insulate a lightswitch when you feel cold air coming out of it


We just tore out a bathtub and drywall. Is it OK to install paper faced insulation next to the hot water pipes of the shower? Thanks.


I want to install lamnant flooring over concrete and im concerned about cold transfering to the lamnant we have carpeting now and its warm but we really want lamnant can we install rigid insulation between the two?

DIY answer guy
DIY answer guy

Is there a problem with spray foaming the underside of your crawlspace? Like if leaks happen or moisture getting trapped, or termites living above the foam. What is your thoughts on how the spray foam would work on a residential level?


Thanks for the tips. Will definitely come in handy with cold weather coming in. I'm specifically interested in installing a radiant barrier.


I installed the Prodex directly on the concrete floor and then installed the laminate flooring directly over it with no issues.
It's been down for three years now. I'd advise filling any cracks or large dips with a concrete patch first.
Let me know how things go.

DIY Answer Guy
DIY Answer Guy

Yes it is OK to install the insulation next to the water pipes. If fact some people install foam insulation on their hot water pipes prior to insulating with fiberglass. Good luck on your project and let me know if you need anything else. Take care.

DIY Answer Guy
DIY Answer Guy

Thanks for the question Judy, and for dropping by.

I had the same situation in my home not to long ago and found that
using a radiant barrier between the concrete slab and the laminate
flooring works best.

This Prodex radiant barrier is only 1/4" inch thick and acts as a moisture barrier,
thermal break, and a bit of cushion when walking on the floor.
It installs with just a utility knife and some foil tape. No adhesives required, as it
floats on the floor just like the flooring.

You can purchase the Prodex radiant barrier at
Be sure to buy Prodex as it has a closed cell foam center rather
than the bubble wrap type.

Also, be sure to tape the seams with foil tape (buy at your local home center).
Remember, DO NOT overlap the seams, just butt them together so you have a
nice smooth surface to install the flooring over.
Once you have the product in hand, how-to butt the seams will make perfect sense.

Also be sure to clean the floor well, prior to installation.

I hope this answers your question.
Thanks again.
Your DIY Answer Guy

PS; Please, let me know if you have any further questions,
and how things come out, as I love to hear about your successes.

DIY Answer Guy
DIY Answer Guy

Spray foam is a very effective insulator but I would not recommend using it in areas where you would be covering up plumbing. Once applied the foam is difficult and time consuming to remove.

I would recommend treating the crawl space for termites prior to insulating. Then to reduce moisture problems install a good quality vapor barrier on the ground.

I recommend using a radiant barrier installed on the underside of the floor covered by faced fiberglass insulation. This will give you an excellent R-value and easy access to any plumbing etc. in the future.

Quick DIY Tip; After installing the fiberglass insulation, use a permanent marker to make notes (on the fiberglass facing) of any plumbing or other utilities that are in the specific bays.

Thanks for your questions.
I'm here to help you.