Transforming An Outbuilding Into A Guest Cottage? Plumbing Budget Considerations

A sturdy, detached building set away from the house might have worked well as a garage, studio or workshop for the former owners of your property. But if your lifestyle leans toward socializing and family activities rather than autos, art and mechanics, turning that structure into a small cottage for guests may be a more appropriate use for the structure. The transformation will take more than adding a few divider walls, paint and a bed. You'll need to have plumbing installed for a bathroom – and maybe a little kitchenette – to make it a truly functional, comfortable guest lodging place.

Budgeting for Exterior Pipe Installation

Putting in pipes for the water supply and drain pipes is not a simple DIY project that can be done on the weekend. Bring in a plumbing service to assess the lay of the land, first. Quite literally, the lay of the land will influence how much excavation needs to be done, as well as how the project is priced. Factors that have an impact on the budget include:

  • The distance between the outbuilding and the water main that needs to be trenched to accommodate the water supply pipe.
  • How much excavation is needed to install the drainage pipes at a sufficient angle to ensure the efficient flow of waste water and solids by gravity to the septic tank or the city sewer pipes.
  • If a sufficient angle cannot be achieved, such as when the building sits in a low part of the property, the cost of a sewage ejector pump is included in the budget.
  • The depth at which the pipes need to be buried in the ground below the frost line to prevent freezing in winter.

TIP:  You may also need to budget for shrub and tree removal to accommodate the pipelines. But restoring the landscaping is rarely a big chore as the plumbing services company is very precise about cutting through and replacing turf where the trench is positioned.

Bringing the Pipes Inside the Remodeled Building

In very warm climates where there's little chance of freezing weather conditions, the underground pipes may be brought to the surface and run up the outside of the building. A hole is cut in the wall to bring both water supply and drainage into the structure.

But in much of the rest of the country, where winter weather conditions could cause the pipes to freeze and burst, the pipes need to enter the structure inside the walls where they'll be protected from the elements. This involves more budget considerations, including:

  • Demolition of a section of the existing concrete slab upon which most types of outbuilding are built.
  • Replacing and repairing the concrete after all the plumbing has been installed.

Providing Hot Water for a Cozy Bathroom

A well appointed bathroom with all the amenities will help make the stay in your new little guest house as comfortable as possible for visitors. A steamy shower or a warm bubble bath is the ideal end a pleasant day of socializing, exploring or simply relaxing in your company.

To accommodate for this type of stylish comfort, your overall plumbing budget needs to include:

  • A hot water heater. This does not need to be as big as the unit in your home which needs to supply baths, showers, the washing machine and dishwasher. Typically a 50 to 60-gallon tank provides ample hot water for single guest or a couple.
  • Typical bathroom furnishings: toilet, sink, bathtub, shower, or a classy tub/shower combination unit.
  • A small sink in the main area of the guest cottage is a nice option to include, particularly if it's accompanied by a microwave and apartment-size refrigerator.

The plumbing may be a major portion of your overall budget for the conversion to a guest cottage. But an experienced plumbing services company can advise you on the most effective placement of the bathroom in the building and other cost-saving measures to get the most enjoyment from this new feature on your property.

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