Florida Section

Good Morning:

There is a project to remove some skylights that were installed in a standing seam metal roof (SSMR), and we are looking for some technical advice. An energy-efficiency project installed skylights on the SSMR and it has leaked ever since. We are looking at removing the skylights, and repairing the holes to be weather-tight without replacing the entire section of SSMR. Is there a recommended way to do this?

TIA

I always advocate against skylights and roof penetrations. Each one is a man-made potential roof leak. If installed properly, they can be good. I am concerned that there is no steel frame around the openings. These openings weaken the roof deck which I am certain is acting as a diaphragm.

My input is based on viewing the three photos and is very preliminary as I may revise my input after reviewing the structural roof framing as-built plans and details.

The system does not look like a standing seam roof. It is a deep metal deck. Maybe a 3" deep deck. Standing seam deck cannot span between the trusses.  

One solution is to use the same deck section (depth, gauge and finish) and nest it over the existing deck. I recommend the new deck length to be a minimum two or three spans with ends overlapping the support by a minimum of three inches. Depending on the structure's location, roof loads (dead and live), wind loads and actual roof diaphragm, fastening to the supports (trusses) should be per legacy plans and secure the edges of the new deck to the existing deck using self-drilling and tapping screws at 6" on center (or as required). Securing the supports can be puddle welded and or with screws. All should be designed and detailed by competent engineers.  

Of course, the roofing including cap sheet, intermediate sheet (if any), base sheet and insulation must be removed and replaced and installed by the roofer who is carrying the warranty of the existing roof. 

------------------------------
Lutfi Mized P.E., M.ASCE
President/Structural Engineer
LPM Technical Services Inc
Merritt Island FL

Original Message:
Sent: 08-01-2024 08:10 AM
From: Arnaldo Vincenty
Subject: Repair skylight openings on SSMR

Good Morning:

There is a project to remove some skylights that were installed in a standing seam metal roof (SSMR), and we are looking for some technical advice. An energy-efficiency project installed skylights on the SSMR and it has leaked ever since. We are looking at removing the skylights, and repairing the holes to be weather-tight without replacing the entire section of SSMR. Is there a recommended way to do this?

TIA

I am attaching additional roof details and plans in pdf.

I always advocate against skylights and roof penetrations. Each one is a man-made potential roof leak. If installed properly, they can be good. I am concerned that there is no steel frame around the openings. These openings weaken the roof deck which I am certain is acting as a diaphragm.

My input is based on viewing the three photos and is very preliminary as I may revise my input after reviewing the structural roof framing as-built plans and details.

The system does not look like a standing seam roof. It is a deep metal deck. Maybe a 3" deep deck. Standing seam deck cannot span between the trusses.  

One solution is to use the same deck section (depth, gauge and finish) and nest it over the existing deck. I recommend the new deck length to be a minimum two or three spans with ends overlapping the support by a minimum of three inches. Depending on the structure's location, roof loads (dead and live), wind loads and actual roof diaphragm, fastening to the supports (trusses) should be per legacy plans and secure the edges of the new deck to the existing deck using self-drilling and tapping screws at 6" on center (or as required). Securing the supports can be puddle welded and or with screws. All should be designed and detailed by competent engineers.  

Of course, the roofing including cap sheet, intermediate sheet (if any), base sheet and insulation must be removed and replaced and installed by the roofer who is carrying the warranty of the existing roof. 

------------------------------
Lutfi Mized P.E., M.ASCE
President/Structural Engineer
LPM Technical Services Inc
Merritt Island FL

Original Message:
Sent: 08-01-2024 08:10 AM
From: Arnaldo Vincenty
Subject: Repair skylight openings on SSMR

Good Morning:

There is a project to remove some skylights that were installed in a standing seam metal roof (SSMR), and we are looking for some technical advice. An energy-efficiency project installed skylights on the SSMR and it has leaked ever since. We are looking at removing the skylights, and repairing the holes to be weather-tight without replacing the entire section of SSMR. Is there a recommended way to do this?

TIA

The latest plans, sections and details confirm my guess about the steel deck. Yes, the water proofing is standing seam over rigid insulation.

I spoke with a roofer friend of mine with many years of experience. His opinion is that it is next to impossible to patch the hole in the standing seam as it will leak again. I agree with him. The best solution is to repair the roof deck as I outlined in my initial responses, add rigid insulation and remove the entire standing seam panel and install new panels. Of course, the rigid insulation and standing seam to be fastened as required to resist roof loads.

I am attaching additional roof details and plans in pdf.

I always advocate against skylights and roof penetrations. Each one is a man-made potential roof leak. If installed properly, they can be good. I am concerned that there is no steel frame around the openings. These openings weaken the roof deck which I am certain is acting as a diaphragm.

My input is based on viewing the three photos and is very preliminary as I may revise my input after reviewing the structural roof framing as-built plans and details.

The system does not look like a standing seam roof. It is a deep metal deck. Maybe a 3" deep deck. Standing seam deck cannot span between the trusses.  

One solution is to use the same deck section (depth, gauge and finish) and nest it over the existing deck. I recommend the new deck length to be a minimum two or three spans with ends overlapping the support by a minimum of three inches. Depending on the structure's location, roof loads (dead and live), wind loads and actual roof diaphragm, fastening to the supports (trusses) should be per legacy plans and secure the edges of the new deck to the existing deck using self-drilling and tapping screws at 6" on center (or as required). Securing the supports can be puddle welded and or with screws. All should be designed and detailed by competent engineers.  

Of course, the roofing including cap sheet, intermediate sheet (if any), base sheet and insulation must be removed and replaced and installed by the roofer who is carrying the warranty of the existing roof. 

------------------------------
Lutfi Mized P.E., M.ASCE
President/Structural Engineer
LPM Technical Services Inc
Merritt Island FL

Original Message:
Sent: 08-01-2024 08:10 AM
From: Arnaldo Vincenty
Subject: Repair skylight openings on SSMR

Good Morning:

There is a project to remove some skylights that were installed in a standing seam metal roof (SSMR), and we are looking for some technical advice. An energy-efficiency project installed skylights on the SSMR and it has leaked ever since. We are looking at removing the skylights, and repairing the holes to be weather-tight without replacing the entire section of SSMR. Is there a recommended way to do this?

TIA

Thank you very much for the support on this. I am very grateful for the response on my inquiry.

The latest plans, sections and details confirm my guess about the steel deck. Yes, the water proofing is standing seam over rigid insulation.

I spoke with a roofer friend of mine with many years of experience. His opinion is that it is next to impossible to patch the hole in the standing seam as it will leak again. I agree with him. The best solution is to repair the roof deck as I outlined in my initial responses, add rigid insulation and remove the entire standing seam panel and install new panels. Of course, the rigid insulation and standing seam to be fastened as required to resist roof loads.

I am attaching additional roof details and plans in pdf.

I always advocate against skylights and roof penetrations. Each one is a man-made potential roof leak. If installed properly, they can be good. I am concerned that there is no steel frame around the openings. These openings weaken the roof deck which I am certain is acting as a diaphragm.

My input is based on viewing the three photos and is very preliminary as I may revise my input after reviewing the structural roof framing as-built plans and details.

The system does not look like a standing seam roof. It is a deep metal deck. Maybe a 3" deep deck. Standing seam deck cannot span between the trusses.  

One solution is to use the same deck section (depth, gauge and finish) and nest it over the existing deck. I recommend the new deck length to be a minimum two or three spans with ends overlapping the support by a minimum of three inches. Depending on the structure's location, roof loads (dead and live), wind loads and actual roof diaphragm, fastening to the supports (trusses) should be per legacy plans and secure the edges of the new deck to the existing deck using self-drilling and tapping screws at 6" on center (or as required). Securing the supports can be puddle welded and or with screws. All should be designed and detailed by competent engineers.  

Of course, the roofing including cap sheet, intermediate sheet (if any), base sheet and insulation must be removed and replaced and installed by the roofer who is carrying the warranty of the existing roof. 

------------------------------
Lutfi Mized P.E., M.ASCE
President/Structural Engineer
LPM Technical Services Inc
Merritt Island FL

Original Message:
Sent: 08-01-2024 08:10 AM
From: Arnaldo Vincenty
Subject: Repair skylight openings on SSMR

Good Morning:

There is a project to remove some skylights that were installed in a standing seam metal roof (SSMR), and we are looking for some technical advice. An energy-efficiency project installed skylights on the SSMR and it has leaked ever since. We are looking at removing the skylights, and repairing the holes to be weather-tight without replacing the entire section of SSMR. Is there a recommended way to do this?

TIA