Drafting Service Files: The 9 Elements of Glazing Project Management
Ordering Materials for a Glazing System is a Complicated Task
Fortunately, many answers can be found in the manufacturer-provided instructions which should be fully reviewed, understood, and referenced frequently throughout the project.
Of course, one can’t rely solely on the manufacturer to provide all of the information for all components of your glazing project. Here is a short list of other components for consideration:
1. SHOP DRAWINGS
It’s important to make sure that you have quality shop drawings. Make sure everyone is on board and they’ve been approved by the architect and meet the project specifications. It is absolutely critical that these drawings be correct. If they aren’t it could end up costing you and your company time, stress, and money.
Make yourself a part of the process. Review the drawing and make sure you fully understand all aspects. Don’t rely solely on your draftsman or drafting company, work with them to make sure that the way your team operates is taken into consideration and that all of your specifications are met.
And of course, make sure everything is labeled clearly to prevent confusion and time consuming reference to other documents.
2. SHOP DRAWING REVIEW
Reviews can be really helpful. Some projects require a professional engineer to review the shop drawings. Alternatively, some manufacturers will offer to review them as well, but these reviews aren’t considered official, so check to see what your project requires. No matter which type of review you acquire, make sure you follow the given information closely to prevent costly problems in the future.
Make sure special attention is paid to glass and safety glazing, especially the type, thickness, and quantity of the glass being ordered. Check with code requirements and make sure that your shop drawings accurately reflect what is needed for your project. It is important that your team not deviate from these specifications after the drawings have been approved by the architect. And always make sure to order some extra glass in case of loss.
Don’t forget to check the wind load charts from the manufacturer as well!
3. STOCK LENGTH TAKE-OFF
Another thing to consider is the optimizing of required stock lengths for ordering the material. Much to the relief of project managers around the world, there are a multitude of software systems out there that can help you figure out what is best for your project. The optimizing software you utilize will typically have a space for each length and their quantities for each component. Prior to inputting that information into the optimizer you will need to identify all of the parts and pieces that are required for the project.
When you sit down to quantify these parts, start with one and finish that component completely. Our recommendation is to work with a variety of highlighters and highlight each part as you enter it into the optimizer.
Don’t forget to order a little extra for your fabrication team, just in case some pieces are damaged in transit or there is a mis-cut. This can save you the time it takes to re-order material.
Glass is taken off using the DLO (daylight opening) dimensions shown on the shop drawings. Consult your installation instructions to find out the “bite” or “inset” dimension required to oversize the glass from the DLO opening. Each system is different and may be different from similar systems of a different manufacturer. Factors such as a framing being an impact system may change the standard bite as well. It is worth double checking with the manufacturer that you are using the correct information. Furthermore the “bite” may be different for different details on the job. Become familiar with the details and the glass sizing requirements.
A spreadsheet is an excellent tool for organizing and quantifying the glass for any project. A labeling system is also a good idea to utilize so your field crew can easily move glass around to the correct frames on the job.
Make sure to take into consideration the type of glass your project needs. Certain types of glass such as tempered or heat strengthened glass may require special attention.
5. ORDERING ENTRANCES
There are a lot of items to consider when ordering your components for a complete entrance. Pay close attention to the specifications, architecturals and your shop drawings. There may be discrepancies between them and an RFI will be required to make sure the proper components are ordered and installed. Furthermore, door hardware can become very complicated and it is advised to develop a strong relationship with your hardware supplier and listen to their advice and experience.
It is prudent to check your shop drawing elevations and floor plans to make sure the handing shown in the elevations match the floor plan handing. This is a very common area for mistakes and mis-ordering. If any doubt exists check back with the architectural drawings to confirm, or send an RFI to the architect for their input.
6. GLAZING VINYL (gaskets)
Glazing vinyl is typically ordered by the roll at either 250’ or 500’ lengths. An easy way to calculate how much vinyl you need is to use your stock length quantities.
This requires knowing which gaskets are used at which locations. Going back to your shop drawings and installation instructions is required for this confirmation. Be careful if you have any untypical requirements on your project such as glass that is not a standard thickness. This most likely will require non-typical gasketing. Your drafting team or service may grab a standard detail from the manufacturer’s online library which may not show your very specific project requirements without modification. Gasket part numbers are an easy thing to not double check or a draftsman to overlook. Take the few minutes to verify these are correct.
7. FASTENERS & ANCHORS
The types of fasteners and anchors required for each project vary and need to be reviewed each and every time. You will have 2 scenarios to work from: either you had the shop drawings stamped by an engineer or not. If the engineer is involved then you will have been given the exact type of fasteners to use, the quantity per detail and applicable edge distances to watch out for. Under this scenario you will make a list of each type of fastener, and per the engineer’s direction count each instance that occurs on the job.
If you do not have an engineer involved then it is time to do your research and make sure that the fasteners you choose to install these frames are adequate, in the correct quantity and located correctly into the material being fastened to. See our website for more details on this process.
Do not assume that if your draftsman or drafting team has fastener information on the drawings that it is correct, and/or adequate for the project.
Finally, make sure you order extra! Fasteners and anchors often get misplaced, dropped or screws strip and a new one must be used. We recommend ordering 5% extra to cover these occurrences.
Sealant selection should be something that is paid close attention to. The sealant is your barrier from the weather to the inside of the building. Improper sealant or sealant installation will most certainly lead to leaks and call backs from your customer. Even if a specific type of sealant is specified by the architect, it is prudent to check all available information to make sure that the materials you are sealing to is compatible with your product, and that the proper steps have been taken to install it correctly. If a primer is called for by the manufacturer, make sure your crew has it, all the tools required to install it and that they actually do it.
Pay close attention to each application, different sealants will be required for perimeter sealants, both interior and exterior as well as structural joints and/or metal connections made during frame fabrication. Your specifications should call out appropriate sealants, and your sealant manufacturer’s rep should be consulted to make sure they agree with the product chosen and its application.
Flashings are taken off from the shop drawings, separated by their material used. Most flashings and/or brake metal are made from aluminum that is finished the same as the glazing system however other materials may be used such as stainless steel. The fabricator will need to know the material types, thickness, length and shape of your flashing required. If you require end dams with the flashing keep in mind the same fabricator can make those for you as well. Your shop drawings should show the dimensions of each leg of the flashing.