Rubber Vs. Foam Pipe Insulation: Which One Is Better?

Ossiana Tepfenhart
by Ossiana Tepfenhart
Pipe insulation is necessary for both energy efficiency and protecting the pipes themselves. Rubber pipe insulation offers more fire resistance, whereas foam insulation can withstand temperature changes more easily. Whether it be temperature resistance, installation, or price, let’s explore the difference between foam and rubber pipe insulation.

When you’re trying to put together a plumbing setup, it’s important to make sure that you have all the little details in order. We’re not just talking about the plumbing’s architecture in terms of pipe layout, either. We’re talking about making sure that your plumbing won’t freeze over. To do this, you will need to make sure it’s properly insulated. The two most popular options are rubber and polyethylene foam. But, which is the better candidate?

Polyethylene foam tends to be more likely to maintain its shape when exposed to different temperatures. However, rubber is more flame retardant and will be capable of handling extreme temperatures. Polyethylene foam is easy to install, but shouldn’t be installed on heat cables or heat tape. Rubber tends to be more affordable.

There is a lot of mixed information about which material is better. If you want to get down to the root of the problem, we’ve got an article that weighs the pros and cons for you.

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An Introduction To Rubber Pipe Insulation

Rubber pipe insulation is the oldest type of insulation that’s still being used. Current insulation that fits in the “rubber” category can come with self-seal or without. People like rubber because of the following reasons:

  • Rubber pipe insulation is easier to install. This is especially true for self-seal rubber.
  • This type of material is also better for high temperatures. Rubber can handle higher temperatures than most foam insulation materials can. This makes it ideal for hot water piping, as well as areas that have heat tape or other similar items nearby.
  • Rubber insulation is also more flexible. If you have a tight corner that you need to insulate or just have a lot of dips and turns, rubber will be a cinch.
  • This is an insulation material that expands and shrinks with temperature. It will vary greatly from time to time.
  • In colder temperatures, you might notice some cracking from time to time. Admittedly, this will happen with rubber in any environment as long as enough time has passed.
  • Rubber is also generally more affordable. Many people find it to be the best way to get the most bang for your proverbial buck.

An Introduction To Polyethylene Foam Pipe Insulation

Foam pipe insulation has been a popular budget-friendly alternative to fiberglass for ages, especially in areas where cold weather reigns supreme. However, there are still perks and pitfalls to this genre of insulation that you need to be aware of. Let’s take a closer look at this one, shall we?

  • Polyethylene foam is temperature-sensitive to heat. PE foam is known for having the propensity towards combustion when exposed to temperatures that are too high. This means you should not use this material to insulate areas that are going to be hotter than 230 degrees Fahrenheit. That includes wrapping insulation on heat tape!
  • This foam comes with self-seal options, but can still be tricky to install. If you are looking for a fast install, stick to tubular rubber insulation. Sawing through foam can be hard. With that said, pre-slit foam will be easy to slide on and fasten to your plumbing.
  • Foam will be able to retain its shape better. Unlike rubber insulation, foam doesn’t expand and contract. In fact, only 3 percent of its size will change with the difference in temperature.
  • PE foam lasts for about six years. This is in contrast to 10 years for rubber.
  • Foam insulation is thicker than most rubber insulation. This isn’t always the case but it’s a good rule of thumb.
  • Polyethylene foam is often better for colder, drier temperatures. With that said, it can lose some of its insulation properties that it has if it gets too wet. So, if you can, you might want to make sure that you avoid wet areas.
  • Some groups are worried that polyethylene foam may be bad for the environment. It also has been linked to toxic substances leeching into indoor air environments, but the amount of chemicals that are released is negligible.

Rubber vs. PE Foam: Which Is Right For You?

Now that we’ve gone over the basics, it’s time to ask the million-dollar question of the day. If you’ve been reading along with us, then you probably noticed that there is no “one size fits all” solution to insulation. Different situations will require different materials. This means that comparing the two is a lot like trying to compare apples and oranges.

In order to make sure that you get the right insulation material, we’re going to parse things out by the type of use that you are looking to have.

Which Insulation Is The Best Go-To?

If you aren’t sure which material to go for, it’s generally safer to assume that rubber tubing insulation will be okay. Rubber isn’t as flammable as PE foam, which means that you won’t cause a fire by wrapping your stuff up in it. Even then, it’s a good idea to look for heat-resistant rubber insulation if you know that it’s going to be around high temperatures.

Which Insulating Material Is The Best For Hot Temperatures?

This should come as a surprise to no one, but rubber is ideal. Because, you know, there is that whole issue of having the foam ignite or melt if it gets too hot. (Did I mention that? Oh, yeah, I did.) If you haven’t gotten the hint already, please do not use foam in areas that are prone to unusually high heat. It’s a bad idea.

If you don’t want to use rubber but still want to go for a high-quality insulation offering, try fiberglass. Fiberglass insulation is heat resistant up to 1000 degrees Fahrenheit in most cases. That’s a far cry from many types of rubber insulation, and also is beyond compare when you’re looking at foam.

Which Insulating Material Is The Best For Cold Temperatures?

If you want to keep your water flowing during colder temperatures, the answer is going to be foam. Foam is good for keeping items warmer during the winter, though rubber isn’t too shabby at it, either. If you are worried about heavy condensation, you still might want to stick to rubber. Even so, anyone who’s ever felt a cold can of soda around a foam koozie will understand why foam works so well in freezing temperatures.

Which Insulating Material Is Best For Wet Regions?

While foam is great to use and will dry out after a certain amount of time, the truth is that it’s not always good for areas that are prone to lots of moisture and humidity. Foam is mold-resistant, but it’s not entirely mold-proof. There have been cases where mold started to grow inside the insulation, only to spread to walls. In fact, it’s a fairly well-known issue that arises from insulation.

The good news is that most foam will not get moldy from regular condensation “sweat.” However, that doesn’t mean that you should assume that you’re good to go. If you want to go with foam regardless, do your best to keep the area clean and dry. To stay on the safe side, you should also regularly clean out the area with a bristle brush. This will help prevent mold growth.

Find out if rubber or cork underlayment is better.

How to Pick the Right Pipe Insulation

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Related Questions

Is spray foam mold-proof?

Spray foam is a unique type of foam insulation in the sense that it’s waterproof. It also happens to be one of the least porous types of foam insulation on the market. However, this doesn’t necessarily mean that it’s mold-proof. Though it’s very rare, it is possible for mold to grow on spray foam.Mold usually grows on spray foam when it can’t seem to find any other areas to spread to. If your spray foam also happens to remain wet for a long period of time, then you might see a change in terms of mold growth. So, keep it dry. It’s a good way to ensure that your insulation remains totally intact.


How well does pipe wrap insulation work?

Honestly, it depends on the insulation material as well as the overall situation. In most cases, wrapping your cold pipes up with foam will help increase the temperature around 2 to 4 degrees Fahrenheit. You sometimes might be able to get more mileage out of your insulation, but it’s rare.At the end of the day, you might be amazed at how much of a difference those degrees make. If you want a more intense heat to your cold piping, then you may need to get some heat tape.


Is it worth insulating your heating pipes?

In most cases, the answer is yes. During extremely cold weather, those heating pipes can freeze up. That, in turn, can cause your pipes to burst. This leads to major damage throughout your home, even to the point of causing flooding. It only takes a single bad snowstorm to cause your piping to burst.So, if anything, consider this insulation as a form of physical insurance on your house. A little bit of insulation can make or break your ability to weather bad weather.

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Ossiana Tepfenhart
Ossiana Tepfenhart

Ossiana Tepfenhart is an expert writer, focusing on interior design and general home tips. Writing is her life, and it's what she does best. Her interests include art and real estate investments.

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