INTERVIEWING A CONTRACTOR FOR WORK ON A HISTORIC HOME
Hiring the right contractor is critical when repairing or renovating a historic building. This list offers recommended questions to help homeowners identify contractors who understand historic materials, preservation approaches, and appropriate repair methods. Select several questions most relevant to your project to ask when interviewing potential contractors and requesting estimates.
RECOMMENDED INTRODUCTORY QUESTIONS
- Are you knowledgeable about historic styles and techniques for the work I need done (for example: trim, masonry, roofing, etc.)?
- Do you have a portfolio of historic restoration work you have completed on homes similar to mine?
- For my style of house, what approach would you recommend for this type of work? (If you are unsure how to identify the style of your home, refer to Salem’s architectural styles.)
- Are there alternative ways to accomplish what I want? What are the pros and cons of each approach?
- What potential problems could arise during this project?
- Are you insured?
- Are you certified or licensed for work in your field?
- Does your firm practice preservation-minded or restorative techniques?
- Do you have experience in related trades (painting, carpentry, roofing, etc.)? What level of experience do you have?
- Do you have established relationships with related trades? (For example, does the painter regularly work with a carpenter when needed?)
- How long do you estimate this project will take?
- Will you personally be doing the work? If not, what are the qualifications of the crew who will be working on the project?
- How will you protect nearby areas of the house, especially historic architectural details?
- Have you done similar work within Salem’s Local Historic Districts? Do you believe the Salem Historical Commission would allow this type of work? (This question is particularly important if your home is located within a Local Historic District, but it can also be useful if you want to meet high preservation standards.)
DEEP DIVE QUESTIONS
Based on the Secretary of the Interior’s Standards for the Treatment of Historic Properties
MASONRY
- What type of masonry materials are present on the building? Examples include:
- Man-made materials: brick, terra cotta, adobe, stucco, concrete
- Natural materials: granite, limestone, sandstone
- Will you maintain or restore the existing masonry materials? If replacement is necessary, will you replace them using matching materials?
- If masonry cleaning is necessary, ensure that the gentlest means possible are used. Low-pressure water and natural bristle brushes with mild detergents are typically recommended.
- If mortar joints are deteriorating, what is causing the failure? Possible causes include leaking roofs or gutters, capillary moisture, or structural settling.
- What type of mortar will be used—lime-based mortar or Portland cement? If mortar joints are deteriorating, identify the cause of the failure. Use compatible materials when repointing, typically lime-based mortar rather than Portland cement.
- Will sound mortar be left intact when repointing, rather than removing it simply to create a uniform appearance?
WOOD & PAINTING
- Will existing wooden architectural features that contribute to the house’s historic character be retained and restored whenever possible? If original wooden details cannot be restored, can matching reproductions be fabricated?
- If wooden features are only partially damaged, can limited in-kind replacement be done rather than replacing the entire feature?
- Can you identify the underlying cause of deterioration (such as water infiltration or drainage issues) before repairs begin?
- When preparing wooden surfaces for painting, the gentlest methods should be used. Hand scraping and sanding are preferred, with more intensive methods such as heat guns or chemical strippers used only when absolutely necessary.
ROOFS
- If the house has historic roofing materials such as slate, wood shingles, or clay tile, will those materials be retained whenever possible?
- If roof replacement is necessary, will the underlying sheathing be evaluated and attic ventilation assessed?
- Avoid alterations to the roof profile that change its architectural appearance, such as the addition of historically inappropriate false gables.
WINDOWS
- Windows are incredibly important to the architectural style of a house. Does the contractor understand what window types are appropriate for the architectural style of the house?
- Most historic windows are made of wood and were designed to be repaired. If a window is damaged, rotted, or drafty, can the contractor repair the defective parts rather than replacing the entire window?
- If windows are drafty, can improvements such as weatherstripping and reglazing be considered before replacement? (See additional resources on historic windows and energy efficiency.)
- Historic windows are subject to movement, friction, and moisture. When restoring a historic window, the wood should be properly reconditioned using traditional preservation methods such as linseed oil.
