Roof Replacement Basics You MUST Know Before Starting

Construction workers on a roof of home
Steven Puetzer/Photographer's Choice RF/Getty Images

Within the home remodel workflow, roof replacement is job number one. Every single project you undertake, from drywall installation on down to the most delicate swipe of paint, will be ruined if you do not protect it properly with a roof.

Know: 5 Basic Types of Materials

Your choice of roofing materials often depends on your locality, as much as on your own personal taste.  Roof pitch (angle) affects the kind of roofing shingles you can use!

For example, wood shake shingles can be used for steeper pitched roofs but not low-pitched roofs.

  1. Asphalt Composition Shingles:  Cheap and easily obtainable, but less attractive than other options due to "flat" appearance.
  2. Wood Shake:  Pricey but attractive shingle.
  3. Metal Roofing:  Still rare, and few roofers know how to install it well; special companies are required for this job.
  4. Slate Roofing:  Highly attractive, and a high-end roofing option; extremely slippery to walk on.
  5. Rubber Slate or "Faux" Slate:  Recycled post-industrial synthetics gaining in popularity.

Decide: Whether To Remove Shingles or Roof Over Them

  • Weight Issues:  The main argument against laying additional layers of asphalt shingles is that the roofing materials can get too heavy for the underlying roof framing.  This can be a structural problem, especially for older houses. It is often said that a triple layer of asphalt shingles is equal to a single layer of slate shingles--an exceedingly heavy type of material.
  • Telegraphing:  One other problem with shingling over existing shingles is that you are essentially repeating some of the surface irregularities that may already be there. If you’re contemplating putting on a new roof, there’s probably a good chance that you may have bubbles, bumps, and waves that you need to get rid of. Putting new shingles over that doesn’t do much for the aesthetic aspect.  One way to minimize this problem is to go over the old roof and correct as many problems as you can. It doesn’t take much more than a hammer, some roofing nails, and a handful of shingles to correct the problem of bumps, gaps, and protruding nails.
  • Saving Work, Reducing Waste:  Stripping off the existing layer and then laying down a new layer adds more work to the process. Not a real problem if roofing professionals are tackling the job—they can strip most roofs in a morning—but if you’re doing the job yourself, it can be rough.

Save: Money and Materials

The cost to replace a roof varies according to your roofing materials (all the way from cheap 3-tab asphalt shingles up to architectural shingles or even slate), the roofing contractor, the pitch (or steepness) of your roof, the area to be covered, and a host of other factors.

A rock-bottom, 3-tab composite roof for a small home may cost as little as $7,500.

Roofing contractors have a great deal of flexibility to negotiate on the cost, so you please feel that you have the license to do so.

Discover: The Best Season For Roofing

A well-coordinated roofing team is amazing--and this is why we pay them to do our roofs.  If roofers only wanted for perfect conditions to install a roof, they would go out of business.  Extending work seasons helps roofers and consumers alike.

In most parts of the U.S., though, optimal roofing season is from late spring to early fall.  

Partially installed areas must be perfectly dry before any covering layers are installed.

The trick behind "expertly shoehorning" in the roofing project is having a large team of professional roofers who can knock out work in hours, instead of days, thus taking advantage of dry periods in offseasons.

Understand: The Basic Process of Roofing

The word "square," when used in relation to roofing, means 100 square feet. 

One reason why roofers speak in terms of squares is because they deal with such vast quantities of materials.  It is pointless to discuss smaller units.

Shingles come in bundles. Three or four bundles of shingles typically comprise a square.

A moderately-sized, professionally installed roofing job might take only 3 or 4 days.

  • Remove all existing shingles, deposit them in a roll-off, and remove.
  • Make minor repairs on the roof if in good condition. If not, replace bad wood with plywood or 1"x6" boards, whichever is applicable to your roof.
  • Install ice dam protection, a barrier of synthetic materials to prevent backed up ice in the gutters which prevents ice-melt from draining away. The ice-melt will permeate under the shingles and cause damage to the inside of your house.
  • Lay down asphalt paper.
  • Apply the shingles - starting at the eaves and working upward.
  • Apply flashing around all areas where leaks might come into the house - against the chimney, stack vents, etc.
  • Install the ridge vent.