From time to time, we compile some of the most frequently asked questions from our clients. We have organized those questions into the following categories:
1. Insurance & Tax discounts (read more)
2. Design characteristics (read more)
3. Testing & Permitting (read more)
4. Cost (read more)
5. Energy Efficiency (read more)
6. Miscellaneous (read more)
7. Technical (read more)
Q: How can I be sure that the windows or doors I am purchasing are impact-resistant products?
A: Before window or door system can be
impact-resistant certified, the products must first meet the American Society for Testing and Materials' (
ASTM) testing standards. The Florida Building Code has been updated to include more rigorous requirements, due to the increase in hurricane frequency and strength in recent years. These changes reflect the lessons learned from weather-related disasters: e.g. all exterior structure openings must be protected against wind-borne debris. Storm shutters and/or
impact-resistant windows and doors are necessary to secure this standard of protection. Inquire to your window dealer, requesting a copy of the Notice of Acceptance (NOA) issued by
Dade County. This document provides a wide range of information on a given product, including dimensions, parts, materials, accessories and installation guidelines. It is the NOA that certifies a product as "impact-resistant" and provides a label on the product that will denote how long the certification will last. You may also download a copy of the NOA from the Miami-Dade county website.
Q: What is the difference between small missile and large missile impact products?
A: Large missile impact - After a product is exposed to a series of impacts with a piece of lumber weighing 9 lbs., measuring 2" x 4" x 6' piece and traveling at a speed of 34 miles per hour. Subsequently, the product is tested to withstand positive and negative wind loads for 9,000 cycles. During this phase, an impact cannot create a hole larger than 1/16 x 5" in the glass interlayer. All windows and doors to be placed in a location 30 within feet above ground level must pass large missile impact testing. Products to be placed in a location exceeding this height must pass either large or small missile impact testing.
Small missile impact - When testing for small missile impact resistance, a product must withstand impact exposure from 10 ball bearings that travel 50 miles per hour. The product must also resist windloads of 9,000 cycles.
Q: What are wind load calculations?
A: Wind load refers to the application of wind pressure on a structure and its components (garage doors, entry doors and windows). Wind-load pressures are measured by pound per square foot (psf) and are displayed in positive and negative numbers because wind pressures are acting both toward and away from a building surface. When the forces act toward the structure, they are categorized as positive pressures, and when wind pressures act away from the structure, they are labeled as negative pressures.
Impact-resistant windows and doors are tested for both pressures, negative and positive. The NOA shows detailed wind-load pressures for each window dimension that passed the test. Wind-load calculations refer to both negative and positive pressures that structural engineers will calculate for us in order to cost-efficiently design a glazing solution for a specific property or structure. Without the wind load calculations, we don't know with certainty if the window meets the potential wind forces during a hurricane.
Q: Do garage doors have to be tested for impact-resistant compliance?
A: Yes, garage doors typically account for the largest opening in a building and are a critical component to the structural integrity of the building's envelope.
Q: How long does it take to get a permit?
A: The turn-around time varies between municipalities. Once we submit the necessary paperwork, it takes us about 1 to 2 weeks to obtain a building permit approval. At times, the process can take longer if permit reviewers have comments about a drastic change in style between the existing windows and the proposed new windows. Each municipality has its own turn-around time and its specific workflow process.
CHOOSING A WINDOW CONTRACTOR
