Most customers don’t know that each structure we build them (pool enclosure, carport, or sunroom) must be custom engineered. Any structure build in Florida must be built to the standards of the Florida Building Code which can vary based on determined, wind zone, environmental zones, and other factors. To ensure that all requirements are met and your aluminum structure is up to code, all permit issuing bodies (city or county) require signed and sealed diagrams from a state certified engineer, before any permit is issued to begin construction. This post will hopefully enlighten you on what the engineering diagrams will look like and what details are on the engineering diagram. Keep in mind these plans consist of 3-5 pages, but for this post we will be looking at the A1 diagram or layout page.
Below you will see an A1 for a screen enclosure with a partial composite panel aluminum roof. This design made this customer happy with an area for outdoor seating in the shade and an area for sun bathing.
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1) This is often the most confusing aspect on the diagram to a consumer. The 11’-11” is size of the aluminum roof portion of the lanai from the house’s roofline to the outer wall. The actual size of this structure is 14×30. Logically you see this 11’-11” and think “WHOA this isn’t what I ordered – its smaller than 14 feet”. The answer is quite simple. The structure’s size is measured by the footprint (ground size), so in this case the slab would be 14×30. Most houses have a roof overhang which must be subtracted from the structures roof size. In this case the house has a 25” overhang which has been subtracted from the total 14’ arriving at a the 11’-11” which is circled.
1.5) This line represents the wall length of lanai. If you add up each section you will see the wall totals 14’ – it is 25” longer then the 11’-11” roof measurement because it goes underneath the 25” roof overhang.
2) This is a door. Doors are not required on engineering (yours may not have doors) because they are not a structural component. We generally put doors on the engineering diagram to assist our craftsman and make sure we are all producing the accurate building.
3) The object protruding out here is an aluminum roof overhang. Aluminum roofs generally must have a 1 foot overhang from screen enclosure walls. The 1 foot rule usually applies to other types of walls (acrylic, glass) as well, but may vary by location.
4) These numbers circled here represent connection details. As we discussed earlier the complete engineering diagrams for a pool enclosure, lanai, carport, or other accessory structure generally have 3-5 pages. Most of those pages are filled up with connection details. The connection details specify things such as what type of cuts, qty of screws, and # of screws, must go at each connection point.
5) 2×5 is the size of aluminum that must be used here. The size of each aluminum member is specified throughout the diagram.
6) Details of structures wind rating: The 150mph hour represents the ultimate wind speeds the screen enclosure must be able to withstand. The 116mph represents the nominal wind speed rating; the amount of wind it can withstand over a 50 year period without an reduction in structural integrity. Keep in mind the wind speed ratings assumes that the structure is properly maintained and free from elemental degradation such as corroded screws or broken cables.
7) These details specify the requirements for the concrete foundation.
8) Specification of the type of aluminum.
9) Specification of the type of screen.
If you have any questions, please submit a comment below and I will be happy to address them.