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Toxics: Lead & Asbestos
Remodelers’ Estimating Guides View all ESTIMATING articles
All estimating is part art, part science. But estimating remodeling relies a lot more on the art side of the equation. That is, judgement and experience are necessary for accuracy. There are a number of factors that add to the cost and uncertainty in estimating remodeling. When in doubt, err on the high side. One rule-of-thumb I learned early in my remodeling career was to estimate how long a job would take and then double it. That turned out to be closer to the truth than I imagined. Important items to consider include:
This usually goes pretty quickly and smoothly, but needs to be done thoughtfully and carefully. In my experience, working slowly and carefully often takes less time than blasting away with sledge hammers and reciprocating saws, and then sorting through the wreckage.
On all remodeling jobs, a good dust barrier is essential to keep the dust from spreading throughout the rest of the house. Care must be taken to not damage existing finishes such as flooring, or causing collateral damage, like accidentally busting through a good wall or ceiling in another room. In estimating, the amount of damage to other nearby finishes may be difficult to predict.
Working in an occupied house with children, pets, valuables, and finishes that need protecting add time and cost to remodeling jobs. Common issues include
- Site access. Delivering tools and materials up a narrow staircase or through a second-story window will be slow (if they fit at all). Working in tight spaces will longer than normal. In urban areas, parking and delivery can be a issue. Also, walking through occupied portions of the house to reach the work site with workers and materials can be challenging.
- Protection of finishes. In addition to a good dust barrier separating the work zone from the living zone, it takes time and materials to protect finishes that are not being renovated. If you damage other areas, your job will unintentionally grow larger and more expensive. The amount of protection required depends on the level of traffic and abuse a surface will be exposed to. In many cases, a heavy plastic drop cloth is not enough. On floors, tub bottoms, and other vulnerable surfaces, a hard layer such as ¼- to ½-inch plywood or OSB placed over a heavy drop cloth is often needed for protection from foot traffic, falling hammers, or miscellaneous debris, bumps, and scratches.
- Job-site maintenance. When working in an occupied home, you may need to spend a lot of time controlling and cleaning dust and debris, securing the job at the end of the day, keeping rain and weather out of open structures, and maintaining a safe environment for children, pets, and others.
Look before you leap – or in this case, before you cut. It’s not always 100% clear whether a wall is load-bearing or not, so you need to do a thorough inspection before cutting into or removing a wall – sometimes cutting a few holes in the plaster or drywall to get a good look at the framing. When in doubt, call in an expert such as an experienced contractor, architect, or structural engineer. I’ve found some pretty strange things over the years. On a large circa-1900 Victorian, neither the architect nor my crew could not figure out what supported the ceiling of the large attached garage. Turns out it was suspended from a roof beam, 20 feet above, by a steel rod –who would of thunk? Also, don’t assume that the original builder understood structural forces. You might find that things have been supported over the year, with a bit of sagging, by a wing and a prayer along with the lath and plaster. Always proceed carefully, with proper shoring (temporary support), to avoid damage to other parts of the structure.
Testing and removal, or “encapsulation” or lead or asbestos can substantially drive up remodeling costs in older homes. Laws vary from state to state, so be sure to check with your local building department when planning and estimating your job. Many states allow homeowners to do their own “abatement” under certain conditions, which can save you a lot of money, but potentially expose you and your family to toxic materials. In some cases, you are allowed to leave the material in place and cover it with new materials – often the cheapest and safest approach. However, some states require expensive safety procedures for all older homes, regardless of test results. So check with your local authorities.
- Lead paint. Most homes built before 1960 contain lead paint, perhaps buried under coatings of modern lead-free paints. However, lead was not completely banned from home paints until 1978. Lead becomes hazardous when flakes or dust are ingested or breathed in after peeling or being pulverized by sanding, cutting, or other demolition activities. Burning off lead paint and breathing the fumes is especially noxious.
- Asbestos. Asbestos was widely used in insulation, pipe and boiler wraps, and other building products until the early 1980s. Other than insulation and pipe wrap, common uses include floor tiles (vinyl/linoleum/rubber), textured ceilings, siding and roofing. Asbestos becomes hazardous when the material is cut, broken, or crushed and becomes airborne. Soft, brittle “friable” asbestos, often found wrapping old boilers and pipes is especially hazardous. Depending on the condition of the material and local regulations, options may included doing nothing, covering the material, “encapsulation” with special coatings, or removal.
You never really know what you’re going to find when you start tearing down walls. The structure may be inadequate, as described above. I found one wall on an ocean-front home framed like a spiderweb – interesting and original, but not very sturdy. Other hidden issues include:
- Wood decay. There are usually clues to significant wood decay before you open up walls and ceilings, but the extent of the decay is hard to determine without tearing into the structure. Inspect any wood that touches earth or masonry. Also look for excessive sagging and settling, bouncy floors, areas of the roof that feel mushy underfoot, or evidence of insect infestation.
- Vinyl or aluminum siding. Beware of what’s behind vinyl or aluminum siding, or the aluminum “coil stock” used to cover exterior wood trim around doors and windows, building corners, and eaves when the siding was installed. The vinyl or aluminum may look great, but what’s underneath is an unknown – ranging from materials in remarkably good condition to severe rot from trapped moisture.
- Old plumbing and wiring. You may find wiring and plumbing runs that were not apparent, and need to be relocated, or just about anything else that may not comply with modern codes and needs updating. Depending on the age of the house, you might find obsolete knob-and-tube wiring, ungrounded electrical systems, or lead plumbing that needs to be replaced, especially in houses over 50 years old. I’ve also found heavy cast-iron drain pipes that had rusted and rotted through. Iron water pipes are often brittle and may break when disturbed. Even modern copper plumbing can be damaged by pitting and corrosion due to hard or acidic well water or other water conditions. Blue stains on plumbing fixtures from oxidized copper may be evidence of corrosion.
- Unusual construction. Materials and building techniques have evolved over the decades, leading to surprises. Behind walls and ceilings, and under floors, I’ve discovered iron and steel, reinforced concrete, rock-hard plasterboard, and other materials where least expected. Some were original to the builder; others added during an earlier repair. The older the building, the more surprises you can expect.
Read more on Hidden Conditions in contracts
Old houses have their charm, but charm can be costly when you have to structurally reinforce it, level it, or match it with new materials. Some issues to consider:
- Square and level. Often nothing is square or level in older homes, so you need to spend time leveling the old (not always possible) or adjusting the new construction to gracefully join the older off-kilter construction.
- Mechanical systems. Tying into old wiring, plumbing, heating systems, chimneys and flues, can be time-consuming and require more work and replacement materials than anticipated. Lead plumbing, knob-and-tube wiring, and other obsolete systems can be difficult or impossible to tie into and, therefore, may need replacement.
- Patching and matching. Patching into existing floors, woodwork, and other finishes is time-consuming, and getting an acceptable finish match can take a lot of trial and error as well as skill. Contracts refer to this delicate process as “match existing,” which is easier said than done.
If you want to use a unit-pricing guide to help estimate your remodeling project, I’d recommend getting one specifically published for remodeling. Look for one that has adjustments for regional costs, different quality levels, and job-site variables. I’m most familiar with Craftsman’s National Repair & Remodeling Estimator and HomeTech’s Remodeling and Renovation Cost Estimator, but there are several others to choose from. (Tip: To save money look for last year’s guide online.
Remodeling estimating guides are the similar to new construction guides, only with additional categories for demolition, repair, and replacement of various components and materials. You’ll find remodeling-only items such as “Break through existing wall and make opening,” In addition you’ll find labor and material prices for retrofitting a skylight or window, adjusting a sticking door, and various types of repairs. Some also provide unit prices for guesstimating whole jobs by the square foot such as kitchen and bathroom remodels, with various deductions and additions for different features and quality levels. Of course, you need to take these whole-job estimates with a big grain of salt.
Some contractors swear by these guides, but most I know only glance at them on occasion to see if they are in the ballpark or to check a task or sub-trade with which they are unfamiliar. For a homeowner with little else to go on, these guides can be a good place to start in budgeting and preliminary estimating. However, with all the unknowns and variability in a real-life remodeling job, you are much better off getting actual bids from contractors or subcontractors for as many tasks as possible.