Complex Ground-Level Additions: Preconstruction (How to Build Additions Guide)

Some additions are so large and complex that they seem more like adding a house to a room instead of a room to a house. If your house is too small, your lot large, and your budget healthy, you may be dreaming of such a project. You may be thinking of a luxurious bedroom Wing; an entertain area with a new living room, dining room, and kitchen; or an in-law unit.

Whatever your plans, a complex addition will take several months to complete and may easily cost more than the original price of your home. Also, restructuring the existing house will complicate the construction process.

This section emphasizes the special guidelines and techniques required for large projects.

A master suite may contain a bedroom, bathroom with custom tile-work seating area, and roomy closets and storage.


Most of the same construction techniques are applicable regardless of the size of a project, but a large addition will require more time, materials, and help than a smaller one. In fact, it will take at least as much effort as building a new home. The following overview assumes that you are familiar with basic techniques and focuses on issues unique to a large addition.

If you hire and supervise your own crew, you will have payroll, insurance, and personnel issues to deal with. If you act as your own general contractor and use subcontractors for all the work, you will spend enormous amounts of time evaluating bids, coordinating schedules, arranging for inspections, and troubleshooting on the job. Even if you hire a general contractor to oversee the en tire project, you will still have to answer questions and keep an eye on the work. Of course, you will probably also be trying to live in your home while all this is going on.

Besides requiring more people than a smaller project, there will be more materials to select, order, and store; more design decisions to make at the last minute; more problems caused by quirks in the existing house; more time until the project is completed; and more checks to write and books to keep.

Getting Ready for Major Construction

To be ready for all this activity, you must do considerable planning well before construction begins. Take time to study your plans so you can make decisions and answer questions whenever the need arises. As you plan the project, consider the following reminders.

Record-keeping. Devise an efficient record-keeping system to track estimates and to account for materials purchases, labor costs (if you hire workers), and overhead expenses.

Personnel. Line up all sub-contractors before construction begins.

Prepare to have workers in and around your home for several months. Make arrangements for them to store tools overnight, get a drink of water, and use the bathroom. Establish rules for using the telephone; you may want the contractor to have one installed. If space is limited on your street, alert neighbors that trucks and cars will need parking during the day. Make it clear ahead of time if you have particular feelings about smoking in your home, a radio on the job, plants to be avoided, and other things that may irritate you, but be reasonable. Assume that the workers will be conscientious and careful.

Cost estimate. Prepare a complete estimate, including all bids, and make sure you have sufficient funds. If you are hiring a general contractor, estimate any incidental costs that aren't included in his bid, such as permits, landscaping, fence repair, change orders, special fixtures, furnishings, or increased use of telephone, electricity, and water.

Schedule. Establish a projected schedule with approximate starting and finishing dates for as many activities as possible.

Major inconveniences. Anticipate times of greatest inconvenience and plan alternatives. If the heating system will be modified, you may have no heat in the house for several days. There will be times when water or electricity must be turned off. Your garage and driveway may be full of building materials.

Site preparation. Prepare the site before construction. Clear away debris. Create easy access paths for carrying materials. Designate areas for storing materials and debris and for setting up equipment.

Doing Layout

If you have some experience in laying out simple decks or a small addition using batter boards and string lines, you can probably lay out a larger addition if all angles are square, the site is fairly level, and the property lines are clear. Even if your addition has a complex shape, you can use simple layout techniques as long as your design is a variation on regular squares and rectangles.

Hire professional help if the design has complex angles, the site slopes, or you have no time to spend adjusting your layout until it's perfect. Consult with a foundation contractor or general contractor with experience in layout or—if time is limited and you can build batter boards quickly enough to keep up—a surveyor who specializes in layout.

Next: Building the Foundation

Prev: Bathroom Additions

Top of Page  All Related Articles  Home