WINDSTORM PROTECTION AND FEMA SPECIFICATIONS
The Federal Emergency Management Agency (FEMA) has issued two documents (P-320 and P-361) with guidelines and specifications for Safe Rooms (also called Panic or Storm Rooms). The International Code Council has a similar publication (ICC 500). But their focus is windstorm, not intruders. Moreover, because they are intended to cover all windstorm cases, including tornadoes, the structural requirements are intended to handle winds of up to 250 MPH. These requirements, unnecessary in much of the country, make such Safe Rooms expensive. Far more important, dozens of people will know of the Safe Room because of the extreme concrete structures that have to be incorporated during the new construction or remodel.
In our opinion, our two design objectives -- affordability and protecting your family from intruders -- are not met with FEMA-based specifications. So we've taken a different path that ensures secrecy, but with a design that is as impregnable as that of FEMA at a fraction of the cost. And it is also a safe structure that can withstand a Category 4 hurricane of up to 157 MPH winds, if the house is built to the Florida Building Code standards.
For very little additional cost, we can strenghten the Safe Room further to protect against stronger hurricanes, including Category 5 storms where the highest velocity ever measured was 190 MPH. And, again, we do this after all the construction and inspections of the new construction or remodel are completed, so only our 3 trustworthy people know about your Safe Room.
Essentially, we assume that the main roof of the house will tear apart and be blown away, so we incorporate the measures described below on our Safe Room, where two walls are external masonry walls (i.e., concrete block) and two are frame interior walls as shown in the image in the second page in this series, entitled "Safe Rooms (Part 2)".
These measures are easier to understand after you see our Safe Room design, where two walls are external masonry walls (i.e., concrete block) and two are interior walls of studs, so, again, you're urged to return here after reading the second page in this series, entitled "Safe Rooms (Part 2)".
- We build a drop ceiling over the Safe Room consisting of planks and 2 X 6 beams 12-inch on center, and this is then lined on the outside with plywood covered with peel-and-stick (self-adhesive) underlayment roof paper and on the inside with ballistic Kevlar. A key element is that each beam, in addition to nails, is tied with hurricane straps to the planks, as shown at top right, and the planks are also tied to the interior room wall studs with hurricane straps.
- To secure the interior stud walls we do 2 things, shown at bottom right. First, hurricane straps are added to the bottom of the studs, connecting these studs to the footer bottom plate as shown (these studs will have been simply nailed to the bottom plate during the just-completed construction). Second, the footer bottom plate of the existing interior frame walls (which will have been nailed to the concrete floor during the just-completed construction) are then screwed to the concrete floor.
