For the lap type gutter expansion joint a gutter end is recessed 2 1 2 minimum into the gutter on one gutter section and fitted flush on the other.
Smacna gutter expansion joint detail.
Figure 1 9 built in gutter expansion joint at wall jan 12 2018 15 05 pm figure 1 8 built in gutter expansion joint.
15 m is a practical maximum gutter length to be served by a downspout.
Following smacna guidelines a 20 ounce copper built in gutter with a 12 inch bottom dimension should have a maximum distance to a fixed point such as a downspout ranging from 17 feet to 20 feet then there would be an expansion joint.
An expansion joint cap is placed on top over the gutter end flanges and the cover plate.
The capacity of a sloped rectangular gutter may be approximated by using a gutter cross section area not less than that of a semicircular gutter and a depth to width ratio of at least 0 75.
The spacing of the expansion joints depends on the size of the gutter and thickness of the metal but a.
Sheet metal and air conditioning contractors national association 4201 lafayette center drive chantilly virginia 20151 1219 tel 703 803 2980 fax 703 803 3732.
Smacna gutter installation instructions step 3.
Right two runs butted together according to smacna the best way to protect your gutter system from thermal expansion is to split any run of 50 ft or more into two separate runs capping both ends and leaving gap between the top edges of the end caps fig 1.
Expansion allowances gutter specific expansion tables based on girth profile metal predicted annual δt expansion of building materials table with various expansion coefficients must be used for fascia and copings with consideration of both metal and substrate flat seam roof expansion guidance over 30 feet use batten seam design to allow for expansion.
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The expansion joint consists of a self adhesive rubber strip to cover a 1 gap joint between adjoining sections and an exterior cover plate.
Sheet metal and air conditioning contractors national association 4201 lafayette center drive chantilly virginia 20151 1219 tel 703 803 2980 fax 703 803 3732.
Install expansion joints at the ends of every forth 4th gutter section which will divide the gutter system into 40 segments.
Left per made expansion joint.
To limit the effects of thermal expansion in gutters 50 ft.
