Standard roof hatch on a pitched roof

We received this set of photos from a customer who used our “off the shelf” Economy Series Galvanized Roof hatch on a pitched shingle roof like you would find in many commercial and residential locations. The standard roof hatch comes with cap flashing and 1” thick rigid fiber board insulation along the curb of the hatch. For this installation, the customer removed the curb insulation from the hatch and bolted the hatch down to the roof. They wanted the most economical roof hatch solution that had a low profile to match the roof slope. Ordinarily we would suggest using a pitch corrected roof hatch on slopes greater than 3/12, but the infrequent use and need for a low profile roof hatch was more important to the customer than the advantages of the pitch corrected roof hatch. Below are some pros and cons of each setup to help you decide which solution is best for your situation.

Open roof hatch showing clearances on a sloped roof

Economy series hatch installed on a shingled, sloped roof

Standard roof hatch on a pitched roof pros:

• Low cost
• Standard sizes most likely in stock for immediate shipment
• Low profile on roof

Standard roof hatch on a pitched roof cons:

• Cannot use roof hatch railing (roof hatch railing may be required by OSHA depending on your site conditions)
• Increased strain on hardware – installation on pitches 4/12 and greater are not covered by warranty
• Decreased opening area due to roof hatch angle (see above photos)

Sample pitch correction options for roof hatch curbs mounting on sloped roofs

Pitch corrected hatch on a pitched roof pros:

• Larger opening for exiting on a pitched roof
• Less strain on the hardware
• Roof hatch railing can be installed on pitch corrected curbs
• Needed for warranty coverage on pitches of 4/12 and greater
• Required for larger roof hatches on pitched roofs

Pitch corrected roof hatch on a pitched roof cons:

• Slightly increased cost (made to order)
• Increased lead time (made to order)
• Taller curb on low end of roof may be more visible from ground level

Using the pitch corrected hatch for your pitched roofs over 3/12 gives you the standard manufacturer’s  warranty and can give you a larger opening to go through, but ultimately it comes down to your specific needs and what is most important for you. If you have any questions, please contact us.