How To Insulate A Cast Iron Bathtub Quickly And Effortlessly

Bathroom, Beginner Info

insulate cast iron bathtub
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Well, if you’ve landed on this post, then the probability is very high that you might be looking for some of the best ways to insulate a cast iron bathtub, right?

Don’t worry, we’re here to guide you in the best possible way that we could.

Irrespective of whether you’re a first-time user or a seasoned professional, after reading this post, I’m sure you would be able to insulate your cast iron bathtub without any technical support or guidance.

Does it make sense?

Why do I need to insulate my cast iron bathtub?

Frankly speaking, insulating bathtubs isn’t a very common practice.

Correct me, if I’m wrong.

However, the younger generation is very keen on insulating their cast iron or other bathtubs because they very well know the importance of saving both energy and money.

The hot water in the bathtub will lose its energy through both the sides as well as the base of the tub.

And, the things become worst if your cast-iron bathtub is set against one of the house’s outer walls.

Coming straight to the point, by insulating your cast iron bathtub, you can keep the water hot for a longer duration as the heat loss to the environment would be minimal.

Moreover, an insulated cast-iron bathtub will also act as a sound barrier.

How to insulate a cast iron bathtub?

Frankly speaking, there are numerous ways of insulating a cast-iron bathtub.

However, the most popular way to insulate a cast-iron bathtub is by coating the outside of the bath walls with spray on foam.

In the next step, you need to fill the spaces between the walls and outer panels by either more spray foam or another more rigid type of insulation.

Nonetheless, before expediting the insulation process, you need to make sure that the plumbing is installed securely and there aren’t any leaks.

What materials are used to insulate a cast-iron bathtub?

As mentioned earlier also, the benefit of insulating a cast iron bathtub is that it is an easy as well as an inexpensive way to enhance the heat-retaining properties of your cast iron bathtub.

Don’t worry, additional insulation wouldn’t be visible and thus will not hinder the look and feel of your cast iron bathtub.

Frankly speaking, there are quite a few good insulation materials including fiberglass, cotton, mineral wool, sheep’s wool, and plastic fibers that can be used for insulating a cast iron bathtub.

However, a majority of our clients prefer fiberglass over other insulation materials as it is the least expensive way to insulate your cast iron bathtub.

The good thing about fiberglass blanket insulation is that it can be easily cut into pieces that will conform to the contours of the tub.

And, the best part is, you can do it on your own without any professional guidance.

Even though you’re an experienced DIYer, I would advise you to wear gloves and a mask because small fibers may irritate both your lungs and skin.

You might be wondering how much fiberglass do you need, right?

Well, for insulating a standard-size cast iron bathtub, one pack or roll would be more than enough.

We always recommend our clients to have a professional installer spray foam the underside of bathtub in order to prevent any last hour misadventure.

The thing that we really admire about the polyiso insulation is that it will slow down the transfer of thermal energy during the winter months.

We highly recommend Polyiso because of its R-7 thermal resistance value.

Moreover, it is able to prevent condensation that may arise due to the difference between the tub water temperature and the exterior temperature.

Well, if you’re on a tight budget and can’t replace your old bathtub, then the best thing that you can do is to remove the paneling around the old bathtubs and apply the foam insulation around the three edges that rest against walls.

Moreover, when insulating a cast iron bathtub, avoid spraying around electrical components or jets.

How to insulate an outdoor cast iron bathtub?

Many of the first-time buyers wouldn’t be aware of the fact that there insulating materials specifically designed for outdoor use.

The good thing about these types of insulating materials is that they also have an anti-reflective characteristics that prevent energy waste as well as enhance the longevity of a cast iron bathtub.

So, you might be inquisitive to know about the best insulating material for insulating a cast iron outdoor bathtub, right?

You can use Polyiso foam (spray-on foam).

It comprise of enough density to provide thermal insulation as well as prevent tub walls from generating a hollow sound.

In layman’s terms, a Polyiso foam is also good at handling unwanted and irritating noises.

For the best result, you can combine spray-on foam with rigid foam such as the regular Styrofoam used for packing and shipping.

However, if you’re planning to install Foil-faced polyiso sheets then you’ll need lightweight frame under the deck to hold the sheets in place.

For filling the space under the cast-iron bathtub, fiberglass could be a great option, indeed.

On the other hand, you should avoid using fiberglass as an insulating material, in case, your bathtub is set against outside walls or on a concrete floor with little or NO THERMAL INSULATION.

Wrapping Up

First and foremost, I would like to thank you for being with us till the end.

Secondly, I would like to bring to your notice that I along with my core team have put loads and loads of efforts in coming up with this idiosyncratic superlative piece of information.

And, in case, you liked our effort please do share this piece of information with the like minded people and the ones who are in need of it.

After all, sharing is caring, isn’t it?

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