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Dominator INSULATED Garden Office

Approx. W5.5m x D3.5m / W18' x D11'6"

(Sizes shown are approximate & full sizes are shown in the product specification)

From £6,729.99 £7,649.99
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From 3-4 weeks

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  • 75mm walls, highly insulated for year round use
  • Customise to a configuration that works for you
  • 24mm double glazing. NOT thinner 14mm glazing
  • Highly insulative SuperFOIL for year round comfort

Found similar for less? Get in touch and we’ll beat it by 10%

Dominator INSULATED Garden Office Overview

Introducing our Dominator Garden Office, designed and crafted to enhance any chosen space, adding the option for more room for a home office, lounge area, or a mix between the two. This garden office offers endless oppertunities, as well as the potential to add value to your property. Our innovative DIY panel system ensures a seamless and stress-free construction process, allowing you to bring your vision to life effortlessly.

 

The Dominator is also fully insulated, meaning you’ll be able to use the space all year round. With the walls, roofing and flooring, all delivered to you in easily manageable panels, each equipped with pre-installed insulation. So you can enjoy your garden office throughout the year, keeping warm in the winter and cool in the summer!

Key Features

  • High internal eaves height - 2.09m (6' 10")
  • Secure, industry leading multi-point locking systems
  • Designed with the DIYer in mind for quicker install
  • Superfelt included as standard
  • Vents supplied for airflow and to minimise moisture
  • 10 Year guarantee on pressure treated floor bearers
  • All fixings included at no extra cost
  • Secure, Industry leading 10-point locking system
  • Sturdy 19mm tongue and groove roof and floor
  • Secure, industry leading 12-point locking system

Additional Information

To ensure the very best quality, we only use slow-grown White Spruce Timber, which is harvested in cold climates to ensure solid, dense log rings. This gives the wood superior strength and longevity, and also a much more consistent colour than the likes of Pine.

Despite the care we take in selecting the very best Timber available, it’s not like predictable brick or cold steel, this natural material has characteristics and quirks unique to every log.

Because our timber logs once fed water and nutrients back and forth from its roots to its leaves, its very nature is to be porous and swell up when it gets wet. Any wooden product will do this throughout its life, but there are a few things you can do to help limit this movement.

These include:

1. A great design!

  • Don’t worry, we’ve got this one covered. We’re experts when it comes to all things timber, so we have designed our products from the ground up with its natural properties in mind.

2. Water Repellent Treatment.

  • How you customise and decorate your product is up to you, however we would recommend that you use an appropriate water repellent treatment. This really helps minimise the amount of moisture that the timber can absorb. Therefore minimising the risk of any major movement.
  • (Please note: water repellent treatment is not the same as pressure treatment, which protects against rot and insect infestation, and which we guarantee for 10 Years!)
  • On pressure-treated timbers, you may notice some subtle striation marks. These marks sometimes appear during the drying process of timbers. Fear not! In time, the marks will begin to fade as the sun starts to lighten the wood.

Timber with Striation marks

3. Ventilation.

  • Keeping your timber building ventilated is no less important than keeping your house well ventilated. This is especially true if you plan to cover up your floorboards with something (double check with an expert, that the material is suitable to do so), as moisture can become trapped between layers of non-breathable materials and build-up, leading to floors becoming rotten.

4. Regular Seasonal Maintenance.

  • Whether you opt to build your product yourself, don’t be afraid to tighten the odd bolt here and there. Your product is a life improving investment, so it’s only right to give it some love and care from time to time. Make sure that it’s properly treated before the rainy months, and you make adjustments to doors and window frames, when needed.

Natural Timber Properties

After building your timber product, this natural construction will begin to ‘settle’. This means that you will likely see some natural timber imperfections appear. These types of natural imperfections can include:

Cracks

Cracked climbing frame timbers

Splits

Split Timbers

Shakes

Timber Shakes

Warping / Twisting

Expansion and Contraction

Please be aware that, as these are natural timber properties they are not considered as defects under our Terms & Conditions (for more information, check out our Terms and Conditions. However, in most cases, these imperfections will not impact the integrity or function of your timber product, and/or can easily be rectified. For advice on how to rectify these and for more support, please get in touch with our Customer Services Team on [email protected].

There is nothing more annoying than being in the middle of building something and finding that you don’t have the right fixings to continue. We include all of the screws, nails and fixings that you will need to put your garden building together – not many of our competitors are that thoughtful. This eliminates the need to worry about the type of screws or the length of nails you might need to get started – it’ll all be with your delivery.

Fixings Included

Wish to customise your Garden room? As the wall panels supplied are of the same size, this means that a wall panel can be replaced by a window panel (for instance) and the wall panel used elsewhere, the doorway (2 panels) can be changed with any mix of 2 panels.

You could put the door on a side aspect and have a wall of windows to the front aspect if that is how you want your Dominator to look.

Customise the Dominator to a configuration that works for you!

Dominator Configuration DIY

A low U-Value means that your walls, roof and floor radiate less heat, in reality, you keep cool in the summer and warm in the winter whilst having lower energy costs. The Dominator has low U-Value walls, roof and floor thus keeping your running costs down. The walls have a U-Value of 0.63, roof U-Value is 0.49 and the floor U-Value is 0.64.

The lower the U-Value the better! Be weary of any competitor products on the market that don’t advertise U-Values.

Fully Insulated Dominator

All of our garden buildings have pressure-treated floor bearers as standard. This treatment prevents the timber bearers from rotting for up to 10 years and causing your garden building to sink. Pressure treatment forces the wood preservative into the timber rather than simply dip treating (essentially just covering the exterior) like many companies still do. Who wants to have to annually deconstruct and re-treat the bearers each year!

Due to this costly but effective process, we can offer our customers a genuine 10-year guarantee against rot and insect infestation on the bearers.  We do however recommend applying a good quality water repellent to the timber to prolong the longevity of the timber. Shockingly many of our competitors still offer untreated bearers to keep their costs down, so beware!

All our Pressure Treated timber is for User Class 3

Pressure Treated Bearers

Rotten Untreated Floor Bearers

Lightweight and flexible. SuperFOIL is ideal for use in Garden rooms like the Dominator. It is preinstalled in the roof and wall panels and is just unrolled across the ground bearers for floor insulation. As it comes on a roll the floor installation is quick and very easily installed.

 

If you had any doubts as to the quality of the insulation, don’t!  Firstly, it’s made from 40% recycled material, so it’s great for the environment, but not only that it’s of a high enough standard that it can be used in homes as part of roof, walls and floor insulation.

 

When comparing competitor products, be sure to check what insulation is used. Some competitors may use cheap materials such as bubblewrap which is nowhere near as effective!

Garden office insulation

The bearers of your garden building are pressure treated to help protect your garden building from the ground up. We provide a 10 year guarantee against rot and insect infestation for all pressure treated timbers.

Unlike some competition, we can offer a genuine 10-year guarantee against wood-eating fungal and insect infestation on pressure-treated timber.

All our Pressure Treated timber is for User Class 3

10 Year Guarantee on Pressure Treated Timber

Purlins are the large timbers used for structural support in buildings. We use very thick, heavy duty roof purlins to support your garden building.  At 140mm x 45mm they are amongst the thickest purlins available on the UK market. Competitors will often use thinner purlins to keep their costs down which means their roofs will not be as strong as ours. Using thinner purlins risks the roof collapsing or sagging during extreme weather – and that’s the last thing anyone wants!

Heavy Duty Roof Purlins

This garden building is under 2.5m high. Why does this matter? Under permitted development rights, buildings under 2.5m high can be placed as close as you want to a boundary (eg. a fence line) without planning permission. Garden buildings that are over 2.5m high need to be placed over 2m away from any boundary (eg. a fence line), which could lead to a lot of wasted space. If you want to find out more about permitted development rights see our planning guide

Both our doors and windows are fitted with internal beading used to secure the glazing in place. This beading style is typically found in uPVC windows and is a proven method of security. However, there are still some companies that externally bead their windows. Allowing intruders to remove the glazing from the outside of your garden house and gain access.

internally beaded windows

Security is important for your garden building, to ensure all your belongings and any valuable equipment is safe. Our uPVC doors feature an industry leading 12-point locking system. Meanwhile, the windows feature multipoint locks with secure key locking handles.

Our 12-point locking consists of four shoot bolts, three mushroom headed espagnolettes, three hook bolts, a locking latch and a 6-pin euro cylinder. The windows feature a multi-point locking system consisting of mushroom-headed espagnolettes which move in opposite directions into metal keeps. Why would you risk your possessions by using less?

So, if you are comparing garden buildings, don’t forget that our uPVC windows and doors offer additional security benefits!

Insutry Leading Multipoint Locking on Windows & Doors Fully Insulated Secure windows

Unlike some, we only use full-length cuts of shiplap cladding on our garden offices, which comes in a substantial thickness of 15mm. The advantages of using shiplap cladding is it is robust and sturdy.

Our cladding interlocks, creating a strong watertight bond that allows rain to run off the office quicker, it also creates an attractive, professional appearance, that’s certain to wow potential clients if you’re running your business from home.

15mm Shiplap on garden offices

Ventilation is essential for the longevity of the Garden Building. This is to ensure airflow and minimise moisture at all times. We have provided ample vents to ensure that condensation is never a problem. Some competitors charge you extra for these or do not even offer them.

Vents Included with cabins

Get your garden office up and running quickly and easily thanks to the full panels provided. No need to waste time building up walls or fixing doors together.

DIY Garden Offices Easy Build Panel System

When constructing your log cabin, you do not need to worry about putting our windows or doors together as they come preassembled. So, you simply need to slot them in after all, we take pride in our DIY-friendly designed products. Many competitor products require you to painstakingly construct the windows, doors and other hardware, such as handles and window trims, and install the glass.

Did you know? You can also add a little character to your windows with some stylish Georgian bars, which we supply as standard, however this is entirely optional and up to you. Not all products offer Georgian bars, so be sure to check the product specification.

OURS:

Dunster House Preassembled Windows, Doors and Hardware

THEIRS:

Competitor Non Assembled Windows, Doors and Hardware

All our garden buildings have been designed on the basis that any competent DIY customer should have no problem installing a product themselves in a short amount of time. You do not have to be an expert at DIY to build a Dunster House garden building, as we do provide you with comprehensive pictorial instructions. We totally understand that DIY is not for everyone therefore, you may want to consider getting in touch with a local carpenter or handyman to install it for you. But before you do, check out our construction video and decide for yourself!

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We recommend a flat, level concrete 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.

 

This garden room is well insulated, but a small electric or fan heater is a good idea to keep the building warm inside. If you choose to install electrics, speak to an electrician about heating.

 

The Dominator Garden Office contains floor, roof and wall insulation made from SF6 SuperFOIL, which is proven to retain heat better than polystyrene or rockwool. The Dominator also features 28mm double glazed units to aid in retaining heat.

 

We offer a genuine 10-year guarantee against rot and insect infestation on all pressure treated timber.

 

No, we do not have any showrooms or display sites. All business is completed online and via our website. If you do have any queries that haven’t been answered with the information provided online, please feel free to call our sales team on 01234 272445.

If you wish to view a particular product, we are happy to arrange a video call or send a pre-recorded video to your email address.

U-values tell us about the heat loss properties of the material you are measuring. The lower the number, the better insulated the Garden Building will be. Find out more here.

We recommend a flat, level base at least 100mm bigger on each side. e.g. A W4.0m by D3.0m garden building would have a base of 4.2m by 3.2m See more details here.

Often, an additional cost is buried within the price when offering finance, thus making your purchase higher priced. This is the reason we do not offer finance and feel that it would not be beneficial for our customers or us. However, we have come up with an alternative method for you where you can use a 0% interest-free credit card to pay off your purchase. For more information, see this article: Do we offer finance?

Dunster House commit to continuously improve the sustainability level of our sourcing, by favouring stricter more credible certification and verification standards, and sourcing requirements. We are committed to avoiding sourcing from unknown or unsustainable sources.

Where possible, Dunster House are committed to procuring wood products that have been certified against credible, internationally recognised standards for good forest management, to ensure that material originates from well managed forests.
In line with this, we preference products certified to the standards of FSC (Forest Stewardship Council) and PEFC (Programme for the Endorsement of Forest Certification).

What about illegal timber?

Dunster House are committed to sourcing only material that is produced, processed and traded according to applicable legislation.

What is your Environmental Responsibility policy?
Dunster House are committed to promoting responsible stewardship of the environment and its natural resources. We are committed to lessening the impact on the environment caused by our own activities, and those of our suppliers.

Do you have a Supply Chain Management policy?
Dunster House will ensure that information about suppliers and material is gathered as part of the RPP. We will ensure regular engagement with our suppliers to ensure compliance with UKTR requirements, working with them to ensure continuous improvements. We will also specify that, wherever possible, that material sourced is covered by FSC and PEFC, to ensure responsible forest management.

Yes, we do! Some postcode restrictions do apply however we are pleased to be able to deliver to many parts of Scotland.

For more information – Where Do We Deliver?

We do not currently offer installation. All our garden buildings have been designed on the basis that any competent DIY customer will have no problem installing a product themselves in a short amount of time.

You do not have to be an expert at DIY to build a Dunster House garden building, as we do provide you with comprehensive pictorial instructions. Also, if you prefer video tutorials, we do have a selection of videos on YouTube which will support you in building your product.

We totally understand that DIY is not for everyone and it can be very overwhelming to start building your own garden product. Therefore, you may want to consider getting in touch with a local carpenter or handyman to install it for you.

If you do take on the challenge to put your garden building together, we are always here to help. Do not hesitate to contact us at any stage of putting your product together and we can provide you with all the assistance you may need. Contact our customer service team via email at [email protected].

Owing to the multitude of possible configurations available for power and lighting we have left these offices for customers to supply and create their own, exactly how and where they want them.

This Garden Office contains floor, roof and wall insulation. The type of insulation we use is called Polyisocyanurate, which is proven to retain heat better than polystyrene or rockwool. This Garden Office also features 28mm double glazed units to aid in retaining heat.

Due to the unique design of a Dunster House product, in the vast majority of cases our garden buildings can be installed without the need for planning permission.

However, there are a few other factors to consider:

As all properties are different in size, shape and style we can only advise based on how we have designed our products, not on your property.

When to consider planning permission:

  • If the garden building exceeds over 2.5m tall – the majority of Dunster House buildings do not exceed this.
  • If you intend on putting an outbuilding in front of the main elevation of your property (as it was originally built or as it was on 1st July 1948) will require Planning Permission.
  • If you live in a listed or graded building
  • If you live in a designated area such as areas of outstanding natural beauty, national parks, world heritage sites and conservation areas.
  • If there is a possibility that over 50% of your garden would be taken up by outbuildings.

Click here for more information on Garden Building Planning Permission in the UK.

Still not sure?

If you are still in doubt, we highly recommend getting in contact with your local authority before making a final purchase.

It is 2.48m (8' 1")

A Garden Office is a garden building used to create an office away from your home, separating your work life from your home life.

A Dunster House Garden Office is made from slow-grown spruce or wood polymer composite, double glazed 4mm toughened glass, and polyisocyanurate insulation (SuperFOIL on our Dominator range), creating a thermally efficient, smart looking product.

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dominator 5.5 x 3.5 garden office measurements
  • Please Note: All sizes quoted are nominal
  • Overall External Dimensions: 5.55m x 3.68m (18' 2" x 12' 0")
  • External Width: 5.50m (18' 0")
  • External Depth: 3.33m (10' 11")
  • Internal Width: 5.30m (17' 4")
  • Internal Depth: 3.18m (10' 5")
  • Internal Area (m2): 16.85m2
  • Ridge Height: 2.48m (8' 1")
  • Internal Eaves Height: 2.09m (6' 10")
  • Roof Thickness: 0.34m
  • Roof Covering Options: Superfelt Included as Standard
  • Overall Wall Thickness: 75mm
  • Floor Thickness: 19mm Tongue & Groove
  • Framing: 45mm
  • Door Walkthrough Height: 1.82m (5' 11")
  • Door Walkthrough Width: 1.55m (5' 1")
  • Glazing Material: 4mm Toughened Glass
  • Glazing Options: 28mm Double Glazing Included as Standard
  • Gaskets: On all Windows and Doors
  • Timber: Slow Grown Spruce
  • Floor Bearers: Pressure Treated for Longevity
  • Please Note: All fixings needed for assembly are supplied
  • Approx. DIY Assembly Time: 2 Days* *This is an approximate time only, based on 2 people. Assembly time may vary depending on season/weather conditions, foundation type, ability of those constructing, etc

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Delivery Information

* Free delivery on orders over £200.

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

Postcodes affected include:

  • TR
  • TQ6, 7, 8, 9
  • EX19, 20, 21, 22, 23, 38, 39
  • LD2, 3, 4, 5
  • PL10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35
  • SA3, 4, 5, 6, 7, 8, 9, 14, 15, 16, 17, 18, 19, 20, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 70, 71, 72, 73, 61, 62, 63, 64, 65, 66, 67, 68 and 69
  • KW
  • HS
  • ZE
  • KA27, 28
  • IV1, 4, 6, 7, 8, 9, 10, 11, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 51, 52, 53, 54, 55, 56, 63
  • PA20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 41, 42, 43, 44, 45, 46, 47, 48, 49, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 80
  • PH32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44

Dunster House delivery map

Green – Free Assisted Delivery

Red – We are unable to deliver to these areas.

Purple – For orders to Ireland & Northern Ireland, please visit our Distributor in Ireland here.

Delivery Service

All of our products are delivered using our own fleet of vehicles, not sub-contractors. We have a large number of vehicles dedicated to delivering our quality products so we can guarantee maximum care is taken during the delivery process.

Our deliveries take place Monday to Friday between the hours of 8:00 am and 6:00 pm.

When the delivery vehicle is unloaded, it is important that you check to make sure all of the items and instructions have arrived and are correct. You will also receive a component list to check your items against. If anything is missing or damaged, it is essential that you note this on your paper work when you hand it back to the delivery driver.

Prices for our delivery services can be found on individual products.

Please note that goods will be delivered to the first point of contact at the front of your property e.g. on your driveway. This must be within 20m from the delivery vehicle (Safely Parked at Kerbside). Our team will be responsible for assessing the risk of carrying out delivery upon arrival at the property.

Should you require further information on our assisted delivery services, please click here to read our Terms and Conditions, alternatively you can contact a member of our Sales Team.

See the locations we deliver from.

Q: Where can I find more information?

A: If you have any questions regarding your delivery, you can telephone our Dispatch Team. Contact details for the Dispatch Team of your nearest branch can be found on your order confirmation. If you need to track your delivery or access your manuals in advance of your delivery, you can visit the Customer Log-In Area of our website /customer-login-area

Thank you for taking the time to read about our terms and advice during this period. We hope you can enjoy your Dunster House garden product for many years to come.

Why Buy From Us?

Buy with confidence! Established for over 30 years, you can rest assured of our knowledge and experience as industry leaders.

On pressure treated timbers*. We don’t dip-treat our timber unlike some competitors. Dip treatment isn’t as effective at protecting against rot and infestation!

All products are uniquely designed and of high quality with many industry leading features you will struggle to find anywhere else!

A UK company and family run business. Our products are designed  and distributed from our 11 UK distribution centres.

Many have bought from us over the last 30+ years due to our superior specification and the fact that our products are designed with the DIY market in mind.

Free delivery on most products*. Delivered to you by our own fleet of vehicles and dedicated drivers.

Inspiration/Customer Stories

Dean’s Garden Cinema Room

View Case Study

Ed’s Garden Music Room and Home Office

View Case Study

Andy and Rose’s Garden Games Room

View Case Study

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* Free delivery on orders over £200.
† Reference to Price on 22nd December, 2023

Dominator INSULATED Garden Office

From £6,729.99 £7,649.99
Save £920