Replaced in a 1900 renovation the slate roof on the white house was replaced with sheet iron in 1804 the copper roof on the old church of christ in philly lasted from the 1830s to 1967.
Smacna duct support on roof.
Snow retention systems zsi safety products s 5.
The types of fittings to be used based on the designer s calculations of fitting losses i e square versus 45 entry taps conical versus straight taps etc.
Ducts are suspended from hangers 12 in.
Roof hvac duct supports unistrut roof support system bases roof crossover stairs crossover ramps s 5.
Duct over 120 inches.
Information required for duct construction 1.
This support can meet nearly all height requirements above the roof surface and is approved for seismic and high wind applications.
Duct over 120 inches determine the tie rod load.
Substrate failed early metal roofs were batten style or flat seamed until.
A copper roof was used on the rebuilt old senate chamber in 1819.
140 2 70 inches rs 28 inches duct over 120 inches.
Duct dimensions duct dimensions shown in the contract.
Sheet metal and air conditioning contractors national association 4201 lafayette center drive chantilly virginia 20151 1219 tel 703 803 2980 fax 703 803 3732.
Seismic supports are not required for hvac ductwork when the i p 1 0 if either of the following conditions is met for the entire duct run.
Tip you can figure the load on a duct of half of the width using table 2 46 and then double the load.
2 500 pa w g.
A comprehensive duct layout indicating sizes design airflows pressure class and routing of the duct system.
Page 2 106 the load is 146 lbs load for 70 inches x.
Featuring a similar design to the time tested model 1 5 the model 3 0 is just as simple to install and is guaranteed to withstand harsh rooftop conditions for years to come.
For all other ducts of any application.
Brackets curved unistrut channel.
Duct construction ductwork and supports shall conform to the hvac duct construction standards metal and flexible third edition 2005.
Or less as measured from the top of the duct to the bottom of the support where.
For all ducts between the supply fan and variable volume control boxes and 1 250 pa w g.
If the designer does not designate pressure class for duct construction on the contract drawings the basis of compliance with the smacna hvac duct construction standards is as follows.
The php d duct support leverages a goal post design with a single crossbar below the duct to support all sizes of square or round ducting cable trays and piping.