The Straight Scoop on Plan Modifications

By Boyce Thompson

Make your home unique by modifying your plan.

Odds are that even if you fall in love with a particular house plan, you’ll want to change something on it. Maybe you’d like more windows on the side of the house that will face the garden. Perhaps you’d like more upstairs hallway space to fit a desk. Or maybe you’d like to bump out the back of the house to create a bigger great room. Make no mistake -- nearly anything’s possible. At a cost, of course. But considering that buying and modifying a pre-drawn house plan is usually more affordable than hiring a designer or architect, you'll come out ahead -- and with a customized home at a fraction of the price. 

You may even be able to modify the home’s basic style. Allison Ramsey Architects has redrawn its popular, three-bedroom, Broad River Cottage plan to better fit a particular neighborhood. A Greek Revival version includes an
 additional cornice, window, and trim detail, along with a few structural changes -- a side porch and a bay window on the dining room. The firm even reversed the plan and did it in a Folk Victorian style.

The reality is that many house plans can be changed (somewhat) by the builder during construction. Often, the builder can also make simple note adjustments on the plan sheets. But it's a good idea to involve a professional to redraw elements of the plan if the changes alter the home’s structure – moving an exterior wall or changing the roof pitch, for instance. There’s too much risk – structural and aesthetic -- in leaving such decisions to someone out in the field.       

“It always sounds so easy to add that third garage or add two feet to the bedroom wing,” says Jonathan Boone of House Plan Zone. Other examples would include flipping rooms or upgrading to 2x6 construction. “But in some cases, those changes can negatively affect other areas that an untrained eye may not catch. It’s just not worth taking the chance on such a large investment to save a few hundred dollars.”

Some designers prefer to perform their own modifications. The added benefit to having the plan designer do the work is that you can go into construction with the most accurate drawings possible, says Jonathan Hyman, the architectural manager for Donald A. Gardner Architects, one of the biggest plan designers in the country. Otherwise, you open yourself to risk if you get into a debate over the design with your builder.

“The drawings for constructing your home are a legally binding part of any agreement you have to build,” says Hyman. “The more items that the drawings are able to detail or reinforce in the construction documents, the better. I would recommend having most modifications done by a professional modification service to precisely convey the home you want built.”
 

That said, many plan buyers rely on builders to make cosmetic alterations – to change brick to lap siding, to move interior walls, or to alter the location of a door. If you know in advance what you want, however, you could have a plan designer “redline” these changes on the house plan for a minimal cost. Most building departments accept these highlighted changes as gospel. That way you are on the same page as the builder when construction begins.  
 

The reality, however, is that you will have to work closely with your builder to detail material selections – the style and color of siding and flooring, molding details, and the detailed design of kitchens and baths. Not all plans detail precise cabinet, siding, and flooring styles. As part of that process builders may move garage door locations or change ceilings heights from flat to vaulted. “The risk is minimal,” says Boone. The builder may also be able to suggest material changes – different French doors or molding patterns -- that achieve the same design intent at a lower cost.
 

The wild card in this process is securing local government approvals. You may have to enlist a local architect or engineer to make sure the plan meets local building code requirements. Most house plans are drawn to national building code standards that are typically adopted by local jurisdictions. But there may be additional requirements, especially when building your home in regions susceptible to floods, earthquakes, or fire, like California.  

If you expect to make major structural changes to a plan, you may be better off buying a set of CAD or reproducible plans. These options usually come with a license that enables you to reproduce the plans to share with your builder, subcontractors, drafter, or engineer. That may also be handy if you need copies for government jurisdictions, trades, and suppliers. It also makes it much easier to work with a local architect or engineer.  

“It’s almost impossible for a plan designer to update plans for local jurisdictions,” says Boone. “There are just too may requirements out there.” Even so, Boone believes it still makes sense for buyers to consult with the plan’s designer before they make major changes. “It just might save them a $10k mistake.”
 

Not all firms can handle requests for plan changes. Architect Geoff Chick is so busy with new projects that he doesn’t have time to handle modifications. He encourages customers to buy CAD files and work with a local drafting service. “I can’t stress enough how important it is to involve a local professional in the design and construction process,” says Chick. “I prefer customers get a structural engineer involved and let the builder sweat the small stuff.”

Learn more about the Houseplans modification service here. Or call 1-800-913-2350 to talk with the experienced Houseplans experts about modifying your favorite house plan design.

Thu Apr 19 00:00:00 PDT 2018