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Cost of Building an Outbuilding

A guide of the process of hiring a tradesman to build an outbuilding, including the costs of labour and materials.

1-20 weeks
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An outbuilding or garden-shed, are perfect additions to a home. You can use it for storage. You can use it for a kids play area. You can also use it as a detached garage. If you wish to have a guest-house/room, this is also the perfect solution, so you don’t have to build an addition to your home. Now that you’ve decided on the outbuilding, what actually goes into accomplishing this addition?

What the job entails

Initially, design work should be considered. If you will use the outbuilding as a room, it needs lighting, flowing water, air/heating, windows, and plumbing. If used as a garage, you might simply need some lighting to see at night.

Determining the use will help you determine what has to be placed in the outbuilding, and which contractor to hire for design/construction. Once all details (interior) are hashed out, the actual design, placement, and construction will commence.

Additional Work

If being used as a home/room, lighting has to be installed, plumbing lines need to be put in place, and heating/cooling must be installed. This requires hiring a plumber, HVAC specialist, and other contractors.

Homeowners must also consider the design and sizing. The outbuilding can be as small as 50 metres to store a car, or tools, or as large as several hundred metres, if you wish to make it into a home/guest room. Bear in mind that your budget will play a vital role in the design, additions, and how you will use the outbuilding.

If you are using it for housing/room, it is a good time to consider investing in furniture, painting, and potentially doing lawn and garden work around the outbuilding. This will eliminate the need to hire several contractors, at different points in time, for each project. You can do everything at once, and reduce the overall cost of the project as well.

Cost and Duration

At a minimum, homeowners should set aside £1000 to construct an outbuilding. Even if being used as a tool shed, you will need light, possibly require running water-, and heating/cooling. All of these tasks require installation and running lines/wires, which will incur high costs.

If being used as a home/room, costs can quickly pile up. New furniture, bedding, linens, items for a kitchen space, should be purchased before you can rent the space, or offer it as a guest room when you have visitors over. These projects will cost upward of £2500, depending on how ornate, and how much detail work you choose to do in the space.

In terms of duration for the completion of the outbuilding, this can greatly vary as well. At a minimum, a simple shed will require 3-5 days for completion and construction. On the higher end, it can take more than 1-month to build a guest suite or room for visitors or to rent to a potential tenant.

These factors must be taken into consideration before you choose to start the construction project. It is also important to set aside time for potential setbacks, as they frequently occur. Especially with large constructions, or design for a home/suite, where you will have visitors sleeping in that outbuilding which is being designed and built outside your home.

Potential Issues

There is always the possibility for setbacks. A big one is the installation of lighting/wiring, water, etc. These jobs require permits, cutting, drilling, and working below-ground.

Therefore, the risk of delays is always present. And, the increase in costs is also something you should factor into the project because many problems do arise with these types of projects.

In some instances, delay in shipment of materials and supplies can also delay the project. If building a home/sleeping space, make sure you set an additional 5-days to 2-weeks for the completion, because there is the possibility that issues with shipment or the availability of supplies is a problem which does occur frequently.

Licensing and permit issues might also arise. Especially if you do not research before-hand, this can greatly set back the completion date for construction, and can end up costing much more money than you bargained for, with some of the construction projects you want to complete, in designing and building an outbuilding outside of your home.

General delays in weather are also possible with such constructions. Due to the nature of the area, rain delays, cold-weather, or possible lightning, might cause setbacks during the construction and delivery of the outbuilding. Although this doesn’t occur often, it is always something that clients should consider, when having an addition constructed to their home, or on their property.

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Sam J

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