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Dunster House Ltd.
Incorporated. 1994
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1. Your warmalog
SAVE £1020
2. Optional extras
3. Foundation options
4. Delivery and installation choices
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Our large Severn Warmalog® is fully insulated to help keep the cabin suitable for relaxation all year round. These extended insulated cabins (connected with a unique metal connector) provide you with two insulated rooms, separated by a high quality single timber door. If you're fed up of the constantly changing temperature in your shed or conservatory, why not see if the Warmalog® is right for you? This new concept of a 62mm sandwich of timber and polyurethane in the wall and floor couples with 24mm toughened glass sealed units made with 4mm toughened glass to ensure thermal efficiency and noise reduction.

Add value to your property with Dunster House's revolutionary "Warmalog®" insulated cabin. This extended cabin can be used in many ways, from garden office to dog grooming haven and everything in-between. The benefits to you and future home-owners are numerous, including better heat retention and more space. It's a fully fledged garden building, complete with two separate rooms.

The comprehensive combination of insulation built into the wall logs, floor and roofing make sure that your new cabin will hold its heat for longer than a non-insulated version. 

This high level of heat retention means that these insulated cabins are well-suited to any number of uses. It could be the perfect place to work from home, or to work out in a home gym. If you reguarly have guests over, having a building for your very own bar would be ideal. Maybe your children need a retreat where they can play to their heart's content - or maybe that's what you need instead. Whatever you need, the Severn insulated cabin will do the job perfectly. 

You will need to prepare a solid base that is square and level to allow you to build this insulated log cabin successfully on your property. You can use concrete or our RapidGrid Foundation system. We recommend a base of 5.0m x 6.0m for this large Severn Warmalog®

The minimum extras needed are a superior quality light coloured 'Barn' paint to seal the outside of the insulated log cabin, as well as a clear silicone sealer for the joints after decorating. These are available from your local decorator supplies. Once you have got those basics organised, the possibilities are endless! Coloured treatment? Dividing walls? Rugs, shelves and paintings? Once your log cabin is built, the only limit is your imagination!

Our thermally-insulated Warmalog® cabins are built of special triple Tongue and Groove logs with a 62mm timber and polyurethane ‘sandwich’. This type of log has better thermal insulation characteristics than competing brands, but at a very reasonable price.

As well as the walls of the Warmalog® Cabin, the 50mm floor and 60mm roof are insulated. The windows are Double-Glazed, with two panes of 4mm toughened glass and a 16mm air gap in a 24mm sealed window unit. These and more thermal design factors give Warmalog® cabins a U value of 0.59. This excellent heat retention makes the Warmalog® the perfect year-round log cabin.

The Warmalog® has an Espagnolette locking system on its wide-opening French Doors, so you can store equipment and furniture safely inside. The roof is held up and strengthened by large Purlin beams, and below your feet, pressure treated floor bearers keep the main cabin raised above the ground.

The Insulated Log Cabin is simple for home owners to assemble, thanks to the insulation being built into each individual log. This is much simpler than other log cabins sold with insulation in sheets.

Log Cabins will never be the same again!

Product Features
Insulated Log Cabin Fully Insulated Log
Insulated Log Cabin Fully Insulated Roof And Floor
Fully insulated
The Warmalog is fully insulated, promoting heat retention and saving you money on your heating bills. We always supply Polyurethane insulation, a superior insulator than Rockwool or Polystyrene. We use 30mm thick Polyurethane insulation, sealing off the building from elements to help save energy. The Warmalog achieves a low 'U' value of 0.59, which shows it has great insulation efficiency.
Severn Grande Insulated Log Cabin Avoid Planning Permission
Our extended Severn Warmalog is less than 2.5m high and therefore exempt from UK planning conditions and permitted development, even if it is close to the boundary of the property. This frees you from legal restrictions and allows you more freedom to choose your ideal site. You can now consider more personal factors such as the amount of direct sunlight it’ll receive, how easy it is to access and its aesthetic appeal.  If you want to find out more about permitted development rights see our planning guide
Insulated Log Cabin Toughened Glass
Insulated Log Cabin Styrene
Toughened glass
We use 4mm toughened glass in our windows and doors for increased safety and security. It is much more difficult to scratch or bend than the plastic alternatives, such as Styrene, Acrylic and Perspex, so it'll preserve the clear view of your garden. The tempering process makes toughened glass far stronger than the alternatives, and harder to break than normal glass. In addition, if it does happen to break, it will shatter into many small pieces, rather than scattering dangerous shards.
Insulated Log Cabin 24 mm Double Glazing
24mm double glazing
The Warmalog comes complete with 24mm sealed window units for increased insulation. This is a single, ready-to-install unit comprising of two sheets of 4mm toughened glass with a 16mm spacer, which allows for optimum convection current between the glass, ensuring condensation-free windows. They are made in our own factory and fully conform to European Standard EN1279, unlike most of our competitors. Properly Insulated windows help to make you make the most of your building throughout the year, and also offer better sound dampening than single glazing.
Insulated Log Cabin Slow-Grown Spruce Wall
Insulated Log Cabin Slow-Grown Spruce Timber
Slow-grown spruce
We use slow grown spruce timber, which is far superior to the commonly used Pine. Spruce is less porous and so less likely to shrink, warp or split and is less susceptible to blue mould. It has fewer knots than pine and is also less resinous, which makes the possibility of sap ruining your clothes or furnishings much less likely. Slowly grown Spruce from colder climates have more densely-packed growth rings and therefore have far greater strength and durability than Pine or “mixed softwoods”, which age and weather more noticeably, leading to a striped effect on your cabin.
Severn Grande Insulated Log Cabin Pressure Treated Bearers
The extended Severn Warmalog features pressure treated floor bearers. These are the parts of the cabin most at risk from damp conditions, so it's essential that they are well-protected! A high-pressure chamber is used to drive protective chemicals deep into the pre-cut lengths of timber, providing pre-prepared long-lasting protection. We guarantee that the pressure treated timber will remain free from rot and insect infestation for up to 10 years!
Severn Grande Insulated Log Cabin Tall Walk-through Height
The extended Severn Warmalog extra tall doors have a walkthrough height of 1.88m (6’2’’) to allow you to move awkward objects or furniture in and out of your new cabin with ease, welcome in more light, and to minimise the chance of bumping your head.
Severn Grande Insulated Log Cabin Avoid Sagging Roof
The extended Severn Warmalog features heavy duty 140mm or 210mm by 45 mm wide supporting roof beams prevent dangerous and unsightly sagging. Just like every other part of your cabin, this important part of the structure will never be glued or screwed together offcuts. We only use single pieces of timber for our purlins to provide you with a strong and stable roof.
Insulated Log Cabin 4-Point Locking System
4-point locking system
Windows and doors are at the heart of your Wamalog’s security, and we design ours to ensure that only welcome visitors can enter your building. We feature as standard, a secure four-point locking system, including: hook, locking latch and two roller cams. We combine this with a 6 pin Euro cylinder, the same type of lock cylinder you would find on the front door of a typical house. Why should your log cabin be any less secure than your home?
Severn Grande Insulated Log Cabin Adjustable Hinges And Friction Stays
The extended Severn Warmalog windows are made with stainless steel friction stay hinges. These aid in keeping the window open in your desired position and removes the need for a stay arm as per traditional timber windows. We also include heavy duty easy-adjust hinges for our doors which allow you to make minor changes if ever required. 
Insulated Log Cabin Storm Braces
Storm braces
To control natural expansion and contraction in the timber, the Warmalog features steel straps on the inside and outside of the cabin known as storm braces, Secured by screws and bolts, these braces are adjusted to spread the timber's natural movement equally across a much larger area, thus avoiding the worst effects of localised expansion and contraction within the wood. 
Severn Insulated Log Cabin Separate Rooms
Separate rooms
The Warmalog Grande provides you with two rooms, separated by a single solid timber door. You must cut the opening for this door yourself, as the wall is not sent to you precut. This multi-room feature gives you many more options for how you can use the log cabin. The 62mm thick insulated walls and solid door means there is some privacy between the two rooms if you want to play loud games or make a telephone call.
What is a Warmalog Insulated Log Cabin?
A Warmalog Insulated Log Cabin is a garden building unique to the Log Cabin industry and exclusive to Dunster House. This unique Log Cabin features a 62mm sandwich of slow-grown Spruce timber and Polyurethane insulation, which come together to create a revolutionary type of wall log. Coupled with 24mm double glazed sealed units made from 4mm toughened glass and roof and floor insulation, this creates a thermally efficient garden building perfect for using all year round.
What size cabin can I have?
We offer a range of Warmalog cabins. The smallest is 2.8 metres wide by 3.0m deep, and the largest is 4.8m wide by 5.8m deep.
How big is this Insulated Log Cabin?
This Insulated Log Cabin’s measurements are: 4.80m (15' 8") x 5.80m (19' 0")
How high is this Insulated Log Cabin?
It is 2.49m (8' 2") high
How much is this Insulated Log Cabin?
This product starts from £8,449.99
What base do I need for this Insulated Log Cabin?
We recommend a flat, level base at least 100mm bigger on each side. e.g. A 4m by 3m building would have a base of 4.2m by 3.2m See more details here. The base can be concrete or made from our RapidGrid Foundation system.
Where can I visit you? Do you have a store near me?
We have 6 branches across the UK. Click here to find the nearest one! Please check with us before you visit if you are travelling to see a particular product.
Do I need planning permission for this Insulated Log Cabin?
Take our quick survey to find out!
How thick are the walls?
The walls of this Warmalog Insulated Log Cabin are 62mm Thick.
What are u-values?
U-values tell us about the heat loss properties of the material you are measuring. The lower the number, the better insulated the Log Cabin will be. Find out more here.

We deliver our products to mainland United Kingdom (England, Wales and Scotland). Some exceptions apply; these are illustrated on the map below.

Scottish areas may be subjected to slightly longer delivery turnarounds, please contact us for details. FREE delivery on selected products over £200 to mainland England and Wales.

Delivery Price

Green - £19.99 delivery fee on all orders under £200.
Yellow - £59.99 delivery fee.
Orange - £84.99 delivery fee.
Red - We are unable to deliver to these areas.

Assisted Delivery

If you cannot provide an able bodied person to offload the vehicle with the help of our driver, we can provide additional manpower with our Assisted Delivery Service. The driver will arrive with some help to unload the lorry, meaning that you can put your feet up.

We offer this service on all items that are delivered, we do not offer this on our couriered products. Prices for this service can be found on individual products.

Should you require further information on our standard or assisted delivery services, please contact a member of our Sales Team.

Scottish areas may be subjected to slightly longer delivery turnarounds, please contact us for details.

Warmalog temperature test - 19/04/2017
Temperature outside the Warmalog Cabin:  11°c
Temperature inside the Warmalog Cabin: 12°c

Temperature after using a 2KW heater:
After 30 minutes: 22° c
After 60 minutes: 30° c

Wall, roof and floor temperature:
The top of the rear wall: 35°c
The bottom of the rear wall: 30°c
The top of the window wall: 32°c
The bottom of the window wall: 30°c
The top of the door wall: 34°c
The bottom of the door wall: 29°c
The top of the full wall: 35°c
The bottom of the full wall: 32°c
The temperature of the roof averaged between 34°c and 35°c
The temperature of the floor averaged between 28°c and 29°c

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