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Underfloor Insulation

Spray foam underfloor insulation

After insulating your roof and your walls, your thoughts will naturally turn to your floors-and with good reason.

Approximately 15% of heat is lost through a floor-making it one of the top 3 priority areas to insulate to ensure your home is as efficient as it should be.

According to the Energy Saving Trust, by underfloor insulation under the floorboards, you will save around £40 a year on average-whilst enhancing your comfort in the process.

Draughts of air are no joke, and although easy to fix in the short-term with sealant, require a more thorough and professional approach to prevent them for good long-term.

What’s more, an adequate barrier of insulation will slow down the rate of heat transfer, leaving the home wonderfully warm in Winter, and refreshingly cool in Summer. Perfect!

Are There Building Regulations I Need to Comply With?

As with most home improvements, floor renovations need to comply with the latest building regulations for your region.

If you hire an accredited contractor, they will arrange this on your behalf, saving you the hassle of checking compliance.

For homeowners in England and Wales, current rules stipulate that you should achieve a U value of 0.25 W/m2K or less.

To achieve this, you will usually need 70mm of spray foam-although this is very much relative, and depends on a variety of additional factors, such as floor type, shape and size.

Spray foam underfloor insulation

Before pressing ahead with the project, always get 3-4 quotes-this will help you get a grasp of the going rate, and better compare products and prices!

What’s the Cost of Floor Insulation on Average?

Although D.I.Y floor insulation is obviously a cheaper choice, the old saying that ‘you really do get what you pay for’ rings true here. 

Moreover, if you use a highly specialised product, such as spray foam, to insulate your floors, you really do need a trained eye to ensure that all areas of application are sufficiently sealed.

Hiring a professional is only going to set you back a few hundred pounds more anyway; according to the Energy Saving Trust, you’re looking at a price range of between £990-£2000 for the average home-although this price will vary depending on your floor type, the level of thickness applied, and whether repairs to your floor are required prior to application.

Always get 3-4 quotes-this will help you to both get a grasp of the going rate for this project and better compare products and prices.

One word of warning: if the price you’re quoted by a company seems too good to be true then it probably is! 

Some cowboy contractors try to cut corners by using a sub-standard form of spray foam so that they can offer an enviable deal. 

Needless to say, this often ends in disaster, with the spray foam substitute performing particularly poorly, and failing to provide adequate thermal protection.

Spray foam underfloor insulation

To assess which floor type you have, you can simply lift up a corner of the carpet and underlay, or if you have a basement, by making your way downstairs to check the floor above

What Are the Main Types of Floor Insulation on Offer?

In general, floor insulation comes in two main types: suspended floor insulation, and solid floor insulation.

For period properties, suspended timber floors tend to be the norm; for newer homes, the ground floor tends to comprise of solid concrete.

To assess which floor type you have, you can simply lift up a corner of the carpet and underlay, or if you have a basement, by making your way downstairs to check the floor above.

Already verified your floor type? Let’s explore the two main floor insulation options in a little more detail…

Option 1: Suspended Floor Insulation

Put simply, a suspended timber floor refers to floorboards positioned on top of timber joists. They are primarily insulated from underneath; however, if this is not viable, you can, in some cases, insulate between the floor joists instead.

Cost wise, the price varies according to whether you go down the D.I.Y route or enlist the help of an expert. 

If you do choose to hire a professional, you’re looking at a price range of between £300-£750, making it a cost-effective choice to consider. 

It’s also important to note that spray foam offers structural support to the floor; a facet which proves invaluable for older homes.

Option 2: Solid Floor Insulation

In contrast to suspended floor insulation, solid floor insulation is a lot more expensive, and is often only added when the floor requires replacement.

In terms of cost, we’re talking of between £950-£2,200 on average, making it best advised if you’re looking to live in your home long-term.

Spray foam underfloor insulation

By using  spray foam to insulate the underside of your floor, you will eliminate convection air currents, whilst simultaneously achieving the required level of ventilation. Sorted!

Underfloor Insulation: Why Spray Foam’s A Better Solution

From unrivalled longevity, to annual savings on bills, spray foam proves ideal for floor insulation-especially for the underside of suspended timber floors, where traditional methods tend to fall flat.

So…how does it work its magic?

Well…by law, all properties must have under-floor ventilation. Unfortunately, these ventilation gaps can cause dastardly draughts in your home-in some cases making them up to 50% less efficient.

One word of warning: you should avoid covering these ventilation gaps. They are designed for a reason, and always with your safety in mind.

By using spray foam to insulate the underside of your floor, you will eliminate convection air currents, whilst simultaneously achieving the required level of ventilation. Sorted!

Spray foam underfloor insulation

By adding a dense layer of spray foam to the space between the floor and the ceiling, the sound will be absorbed and lessened, creating more peaceful conditions inside

What Else Can Spray Foam Offer For Underfloor Insulation?

Benefit No.1: Adds Structural Integrity to Your Floor

You’ve probably heard that spray foam is ideal for roof restoration-but did you know that it can support your floor joists as well? 

Moreover, its superior seal means that you won’t have to make do with carpets-instead, you can show off your floorboards to their full advantage, safe in the knowledge that they won’t be cold to the touch.

Benefit No.2: Works Around Pipes and Wiring:

Unlike conventional methods of insulation, spray foam has been formulated with hard-to-reach spaces in mind, enabling you to insulate around pipework with ease.

Benefit No.3: Minimises Thermal Bridging from Your Floor

Spray foam is the only product on the market that can provide an airtight seal for your floor. By doing so, it minimises thermal bridging, ensuring heat is retained within.

Spray foam underfloor insulation

Does peace and quiet seem like an all too distant reality? With spray foam insulation, achieving a harmonious home is the rule rather than the exception

Can Spray Foam Be Used as Underfloor Sound Insulation As Well?

Absolutely! In fact, by insulating your floorboards with spray foam, you’ll ensure your property meets the very latest building regulation standards for soundproofing.

Even though the rules depend on the material of the floor, in general, the new rules from 2003 and 2010 stipulate that all new build properties (or those that have been converted), comply with certain soundproofing criteria for floors.

If noise is generated upstairs, it needs to pass through the floorboards and the cavity, and then the ceiling before it reaches you. Usually, this is relatively obstacle-free.

However, if a dense layer of spray foam is added to the space between the floor and the ceiling, the sound will be absorbed and lessened, creating more peaceful conditions inside. Sorted!

Book a free, no obligation survey to know exactly how spray foam insulation can boost the comfort of your home.

We are ready when you are.