SOLDERING 101: Essentials for Roof Soldering


50/50 quarter pound bar solderSolder is defined as a low melting alloy that is used to join two pieces of metal together.  In the roofing trade, the most common makeup of solder will be a mixture of tin and lead.  The 3 most common solders for roofing are listed below

  • 50sn/50pb  (Tin/Lead) Solder – 361° – 421° F working range
  • 60sn/40pb (Tin/Lead) Solder – 361° – 374° F working range
  • Pure Tin (96% Sn, 4% Ag) Solder – 430° F working range

For a more in depth description of the differences in these solders, Click Here

Forming Equipment

Forming equipment can come in a variety of shapes and sizes and it’s main purpose would be to form the seam that is to be soldered. Common forming tools include

The way a seam is formed can be a major factor in getting a successful, watertight solder result.  A couple examples of seam types are listed below. Note that when working with 20oz copper, it is recommended to lap and rivet seams that are going to be soldered. You should also rivet seams that may be put under tension.


The use of abrasives will aid in cleaning any debris or oxides from the joint that is being soldered. Feel free to use an abrasive wheel (drill attachment) or a pad to work the joint before any flux is added.  This will be particularly important if the metal is not fresh from the coil and has had time to develop oxides on its surface.

Flux & Flux Bottle

Flux: A substance that facilitates soldering, brazing, and welding by chemically cleaning the metals to be joined. 

One of the most important aspects of any soldering job, the flux will promote “wetting” of the solder joint and allow the solder to flow and adhere to the surface free of contamination.  Often times in roof soldering, flux is &#