A simple guide to estimating

Chapter 4

For most homeowners, the urge to "do it yourself" comes from a desire to save money. While some people are craftsmen and want to put something of themselves into the project, most are hard-pressed to do any of their own repair work. Many people ignore a problem far too long because they don't know how to fix it themselves and are reluctant to spend the money to hire a professional.

Most of the repair and improvement projects that are appropriate for a home require a substantial amount of expertise, and most people do not know how to do these things. Still, some things are worth trying if you have the time and the energy. Some things are definitely not worth trying yourself unless you are already an expert. If you tackle something beyond your ability, the result could actually damage your house, or at least cost more than the original bid to correct. Think of repair and improvement projects as being on a continuum, with "easy" at one end and "hard" at the other end. Where you land on the scale may vary from week to week, let alone year to year. Do you have the time? Are you healthy? (a sprained ankle from a skiing trip will slow you down for a while.) Is bad weather coming soon? These things will all affect how you feel about a "do-it-yourself" project at any given time.

Deciding how to approach a project requires a clear understanding of what is involved. If you are planning to hire someone, you should have some grasp of the magnitude of the job. Even skyscrapers can be broken down into manageable components. Let's look at how to assess a job.

Estimating

The first thing most people want to know is how much money they will save by doing the work themselves. If the job is mostly labor and you have the skill, you may be able to save quite a bit. However, a professional may be able to get better prices on materials, have the right equipment already on hand, and do a better-looking job. Painting is one of the jobs that homeowners often do themselves, but the results vary widely according to the knowledge and effort put into the job. Do a little homework before you make a final decision about doing a job yourself.

Small Jobs

You can create a simple estimating matrix for a small job. The cost can be split into categories, and the categories estimated individually. The four categories you will set up include Labor, Material, Equipment, and Subcontractors. Labor represents the work of others when you pay them by the hour and you are responsible for what they do. Material includes all the parts that you must buy to use in the project, including fasteners, clean-up supplies, etc. Equipment includes tools that must be rented or purchased, and subcontractors are the people who provide everything you need for a portion of the project and are completely responsible for that part. A subcontractor gives you a bid that includes material and labor, and directs and supervises the persons doing the work.

Suppose your back fence blew down in a windstorm. You need to get the fence replaced soon, but you are short on cash and think you might save some money if you do it yourself. How much will you save?
First you go out and measure the fence--we'll say it's fifty feet. We will assume that none of it is salvageable and that you can't get your neighbor to contribute. You decide to replace it with six-foot-high redwood fence boards. You call "Contractors--Fence" in the Yellow Pages and get prices starting at $20 per foot. This is a total job cost of $1000. Now you want to figure what it would cost you if you did it yourself.

You will provide your own labor, and you're not sure how long it will take, so let's start with estimating the material. Most fences have one post every eight feet (measured from center to center), so you will need seven posts, except that you will be short two feet. If you stretch the distance between the posts to make up the two feet, you can't use 8' two-by-fours between the posts (stringers), so you'd better get eight posts. These will be eight-foot four-by-fours. You will want three stringers between each post, so that's three times seven, or twenty-one redwood two-by-fours. You also want 50 lineal feet of fence boards, which are probably one-by-sixes (actually 5 1/2"), so you will need at least 110. Unless you can hand-select these, you will need a few extras to be sure you have enough good ones, so let's say you need 120.

If you use galvanized brackets to secure your stringers, you need two per board (42 brackets). You also need galvanized nails in two sizes; small ones to secure the stringers to the brackets and larger ones to nail the fence boards to the stringers. If you decide to cement the posts, you will need a couple of bags of ready-mix for each post (2 x 8 = 16). How is our material list shaping up now?

 
Materials List
Item
Quantity
Unit Price
Total
Posts
8
8
64
Rails
21
4
84
Fence Boards
120
1
120
Brackets
42
1
42
Nails
5
1
5
Dry-mix Concrete
16
3
48
Total
363
 

You now have a material total for your larger matrix. This assumes that you are not painting the fence after it is finished.
You don't have a pickup truck, but the lumber store will deliver, so you keep going. Since you have no way to get rid of the old fence, you subcontract that job. This person uses his own vehicle, and agrees to haul it away for a flat fee of $125. This goes in the "Subcontractor" column.
You own a shovel, a saw, a hammer, and a level, but you need to rent a post-hole digger (the "clam-shell" type, not a powered one) and a wheelbarrow. This costs $20 for one day. (You had better plan your time well, or that cost will double!) This amount goes in the "Equipment" column. So far, you figure the fence will cost you over $500 plus your labor, so your time is worth less than $500.

 
Estimate Matrix
Item
Labor
Material
Equipment
Subcontractors
Total
Fence
?
363
20
125
508
 

You won't know what this represents as an hourly rate until you do the job, but you can begin to speculate. Odds are the job will take longer than you think it will! Your hourly rate will probably be between $10 and $20 per hour, assuming you finish the job. Don't forget the aggravation factor. This is hard work, and your hands may get blisters. Your shoulders will ache, and if you don't finish on schedule other aspects of your life may suffer. It's easy to underestimate time and materials. If you decide to "do-it-yourself" to save $500, and in the end find that you only saved $300 and were miserable the whole time, it may not be worth it. If you successfully saved $500, enjoyed the project as a change of pace from your desk job, and beam with pride every time you look at the fence now that it's done, you made the right decision.

The more you can identify the "hidden" costs of a job, such as sealants, clean-up supplies, additional impulse purchases when you are at the home improvement store, and extra trips to the lumber yard because you forgot something, the better choice you will make in deciding what to do yourself. Contractors usually include a "contingency factor" in their estimates as a cushion when preparing a bid, just in case they forgot something or find an unexpected problem on the job.

How much do you think a contractor should add to his bid to allow for the time that the homeowner spends distracting his workers with questions and chit-chat? How much should be added to cover the tool that breaks down in the middle of the job, and has to be taken in for repairs before the job can be finished? These are some of the factors that cause contractors to come up with different bids for the same job, and why at first glance bids often seem to be high. Contractors need to make a living, and if they bid too low they risk actually losing money. Contractors must also cover their overhead, including office supplies and forms, insurance costs, vehicle maintenance, tool replacement, clerical staff, payroll taxes, and all the other costs of doing business.

The contractor also spends a lot of time on your job that you don't see, such as preparing the estimate, calling subcontractors, picking up materials, etc. A client who fails to recognize these legitimate costs of doing business may feel like he is somehow being cheated. Ironically, a well-organized and efficient contractor can make the job look almost easy, while a poor contractor will seem to be working harder because he is always dealing with problems. If your job is half-way completed and things have not been going well, you would be more than ready to "pay extra" to have avoided the unnecessary hassles. If you pick a good contractor at the beginning you can avoid a lot of problems, even if the bid was not the lowest one you received. See Chapter 6 for more information about selecting a contractor.

Now that you are aware of some of the many things that can affect a bid, we can return to our sample estimate. The fence-building example above may represent only one part of a larger job. You can fill in a larger matrix with a separate line for each trade or specialty. Any system that allows you to include everything in your estimate is going to give you a good roadmap to your project. This is the "bottom line" that causes contractors to sink or swim--it is critical to include all the costs, because once you start you need to be able to afford to finish!

 
Larger Matrix for Entire Job
Item
Labor
Material
Equipment
Subcontractors
Total
Fence
?
363
20
125
508
Sidewalk
500
250
75
0
825
Install Sprinklers
0
0
0
750
750
Landscape Plants
?
250
75
0
325
 
Total
2,408
 

Your contractor will be responsible for the accuracy of the final estimate if he bids a fixed price for a completed job. You can also see the advantage of getting several bids. If one contractor's bid is much lower than the others, there's a good chance he forgot something. A contractor who is losing money on your job is more likely to have problems that affect the job, especially if his cash-flow is tight. You don't want your contractor to go broke halfway through your project. See Chapter 6 for more information on contracts.

Painting is a job that can be tempting to do yourself, even for an inexperienced homeowner. Remember that a professional painter may get a larger discount on the paint and supplies, and will already own the necessary equipment (ladders, drop cloths, brushes and rollers, spray equipment). If you start such a job yourself without a true idea of the time involved, you may find yourself at 10:00 pm on a Sunday night with a room still unfinished, not quite enough paint left to finish that last wall, paint on your natural-finish baseboards, not enough light to see what you are doing when you are rinsing your tools, and a generally cranky outlook on life. Was it worth it to do it yourself? The answer may still be yes if the job turns out okay and you saved a fair amount of money. The important thing is to know what you are getting into before you decide. It's even worse if you do-it-yourself and realize after the job was done that the unexpected extra costs and hassles resulted in no savings at all.

Large Jobs

Estimating large jobs is more complicated, because there are so many things to remember and the stakes are higher if you don't do it right. Your contractor should be responsible for estimating and bidding your job, but the more you understand the process the better your chances of getting what you want at a fair price.

The "Sixteen Categories" For larger projects, some estimators use a system from the Construction Specification Institute (CSI), which has sixteen general categories with many subcategories. This system is widely used in the construction industry and allows architects, suppliers, and contractors to communicate within a consistent framework. The general categories are listed below with a brief explanation:
  1. General Requirements: usually the kind of information that relates to all jobs, such as the statement that all changes are to be in writing or that the contractor is responsible for obtaining permits and scheduling inspections.
  2. Site Work: grading, tree removal, demolition of unwanted structures, irrigation systems, driveways, drains, etc.
  3. Concrete: foundations and flatwork (sidewalks, patios).
  4. Masonry: brick walls, concrete block.
  5. Metals: fabricated steel, such as handrails.
  6. Wood and Plastics: everything from framing lumber to glued laminated beams to laminated plastic countertops.
  7. Thermal and Moisture Protection: insulation, roof coverings (shingles, tar and gravel, roof tile), siding, unit skylights, and sealants all fall into this category.
  8. Doors and Windows: there are far more choices for doors and windows than you might think. There are wood, metal, and plastic doors and windows, garage doors, folding doors and grilles, replacement doors and windows, and a full range of finish hardware for doors. Check companies that specialize in these items to get ideas for the full range of possibilities.
  9. Finishes: Interior finishes include lath and plaster or drywall (gypsum board, also called sheetrock, that is taped and textured). Paint and stain will create a distinctive appearance, as will floor coverings such as tile, vinyl, and carpet.
  10. Specialties: include zero-clearance fireplaces, woodstoves, louvers, vents, and screens, tub and shower doors, and closet specialties.
  11. Equipment: includes residential appliances, central vacuum cleaning systems, and security and vault equipment.
  12. Furnishings: includes drapery and certain hardware items.
  13. Special Construction: includes saunas, wine storage rooms, and glazed structures such as sunrooms.
  14. Conveying Systems: residential elevators.
  15. Mechanical: includes plumbing (including fixtures), and heating, air conditioning, and ventilating systems (HVAC).
  16. Electrical: includes the entire electrical system, including lighting fixtures and alarm and detection systems.
 

This system works pretty well for people who are used to it, especially those who do commercial work. It can be a little confusing for someone who is trying to estimate a simple remodeling job. One advantage to being familiar with this system is that many material catalogs are organized this way. The Sweet's Catalog File is an industry reference that is made up of catalog cut sheets from many different manufacturers. This multi-volume residential reference has ads for almost every specialty used in remodeling. Other organizational systems are also useful. The goal is to have enough of an idea of what is included in your project that you don't forget anything.
Even if you are intending to work with a contractor, you can do a lot of planning if you have a list of topics to work with. Here is a list to run through for a room addition based on the "sixteen-category system," to give you a sense of how it organizes your estimate.

Example: A Room Addition

This system works pretty well for people who are used to it, especially those who do commercial work. It can be a little confusing for someone who is trying to estimate a simple remodeling job. One advantage to being familiar with this system is that many material catalogs are organized this way. The Sweet's Catalog File is an industry reference that is made up of catalog cut sheets from many different manufacturers. This multi-volume residential reference has ads for almost every specialty used in remodeling. Other organizational systems are also useful. The goal is to have enough of an idea of what is included in your project that you don't forget anything.

Even if you are intending to work with a contractor, you can do a lot of planning if you have a list of topics to work with. Here is a list to run through for a room addition based on the "sixteen-category system," to give you a sense of how it organizes your estimate.

The "Work Write-Up" Style of Estimating

Another way to describe your job is by writing a narrative of what you want. The contractor will do the design and estimating based on your description. Instead of organizing the job by the "sixteen categories" or another system designed to facilitate estimating by the contractor, you simply describe the desired result. You may go from room to room noting what is to be done, such as "paint the bedroom," "install new smoke detector," "replace the living room carpet" and so on. Notes such as these will help your contractor get started working with you and will help you remember all the things you want to do. Your specifications should require that the contractor be responsible for all the materials and labor needed to complete the job even if you have done a simple material list of your own during your planning process.

A work write-up for a room addition would still give a contractor a good idea of what you envision, even if it does not have the same level of detail that a complete estimate would have. It can serve as a bridge between your best ideas of what you want and a more complete design and estimate done by a contractor. If you write a list or a few paragraphs before meeting with a builder, it will help you both visualize the project. If you want to expand the living room and change the entrance, you can note that you want a French door to the patio as well as a new front door. You can combine a narrative ("I want a larger living room, more storage space, and a good view of the garden") with a list of items ("tile floor, extra electrical receptacles, skylight in hall") to help direct your planning. The contractor or designer will certainly have other suggestions as you review your write-up, but the time you spend thinking in advance will help facilitate your time with a professional.

You do not have to be a professional estimator to plan a job. For small projects it will help to have some idea of the costs involved, especially if you are deciding whether to do-it-yourself. If you make a mistake in estimating, it will be annoying but probably will not have a serious impact on your overall financial stability. For larger projects you will be relying on the contractor to do the actual estimate. Preparing a "ballpark" estimate in advance can help you be more realistic when you begin to talk to contractors, and focus your attention on some of the many choices you will be asked to make when you are setting up your project. Even if you don't prepare an estimate of your own in advance, you will be aware of the complex factors involved when the contractor does it for you!

 
Next Chapter: Plans and Specifications
 
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