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  • OffPOD

Insulated Garden Rooms

Updated: Nov 8, 2022

Garden room roof being insulated by man wearing a helmet and a dust mask

Many people may think that the most important aspect of their garden room or garden office is the way it looks. We argue that although this is important, what really matters is what is going on inside the walls of a garden room and its structure. The benefits of a well-insulated garden room should never be underestimated.

When buying a luxury garden room like those offered by OffPOD, and spending £30,000 or more, it is important that quality for longevity is a focus. With Offpod, it always is. Naturally, if one is spending a large figure, then a space which is useable all year round Is essential. This is where we pay particular attention to detail when designing and engineering our bespoke garden rooms.

There are many different types of insulation on the market and it is important that you know different levels of effectiveness that they have. Moreover, you want to know the insulations thermal retention when it comes to keeping your room warm in the winter and cool in the summer, thus, being as energy efficient as possible.

Some garden room manufacturers may tell you their garden rooms are insulated but do not go in to any more detail. This should always raise a red flag given how significant it is regarding the functionality of your modern garden room. If they don’t tell you the specification of your insulated garden room, then you need to ask!

At OffPOD, we are proud to talk about the type of insulation we use and why. Ultimately, we want our customers to ensure they are making the right decision and end up with an all year round garden room.

We have seen garden room manufacturers using 40mm fibre glass insulation on their builds which will guarantee nothing other than your garden building being very cold the winter. Fibre glass insulation is one of the cheapest on the market and 40mm is nowhere near thick enough to effectively insulate a garden room no matter how good the insulation is.

When constructing our garden buildings we never use anything less than 100mm of super insulating rock wool. This type of insulation is between 25-50% more expensive. Along with it being more expensive, the R value of rock wool(which is what really matters) is 22-37% higher. The R-value is a measure of resistance to heat flow through a given thickness of material. So, the higher the R-value, the more thermal resistance the material has, therefore, the better its insulating properties. Quite simply, rock wool is a significantly better insulator than fibre glass.

The benefits of Rockwool do not stop with its insulating properties. If your garden room is situated close to a boundary fence , you want to ensure that your room feels private. You don’t want noise pollution entering the room and disturbing you if you are using it as a garden office and likewise you do not want people outside the room hearing every word of your conversations. This is another positive whereby the performance of Rock wool completely exceeds that of fibre glass.

As part of our bespoke, fully customisable service, we also offer our customers the the option of upgrading their insulation package to a combination of Rock Wool and Polyisocyanurate insulation (PIR) . PIR insulation has superior insulating properties and has very good fire resistance properties. Polyisocyanurate (PIR) is one of the most efficient insulation material used in construction. PIR insulation provides acoustic and thermal properties, rigidity, durability and excellent compressive strength. PIR insulation boards require approximately half the thickness of traditional forms of insulation to meet the same level of thermal performance. The increased performance does come at a cost though. PIR insulation usually costs in the region of about 40% more than Rock Wool and also can be labour intensive when it comes to installing. Due to its ridigty, PIR insulation needs to be cut down with a hand saw when applying to areas which are a different size or shape to the boards.

R-Values per inch

Fibre glass- 2.2-2.6

Rockwool- 3-33

PIR- 4.3

If you are looking to buy insulation for a project of your own then be sure to check out or both have an extensive range of insulation for your home projects at a great price and deliver nationally.

To conclude, if you are in the market for buying a garden room then be sure to ask the company details about the selected insulation. This will straight away tell you if they have a focus on the quality of their builds and will ensure that your garden room is useable all year round.

Offpod: conscious precision.

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As the founder of a construction company specializing in steel-framed garden rooms, extensions, and annexes, I have dedicated myself to delivering bespoke, high-end products tailored to each customer's unique needs. My role encompasses a broad range of responsibilities, from conducting site surveys and closing sales to managing SEO and website design, all aimed at ensuring operational excellence and driving profitability.

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