Last month, in Part 1 of the Guide to Measuring Glass Partitioning we looked at the first step: Measuring openings and site survey. We looked at taking measurements from various points in an opening and going through all the necessary checks on site in preparation for the glazing channel track installation. We also looked at key steps to making a full site survey.
Once the glazing track is in position, the glass is ready to be measured for production and then installed. For Part 2 of this guide we will look at the second step: Measuring glass for production and installation.
Above: An basic example of a glass partitioning drawing, with the information needed to produce the glass panels and where each is positioned.
Before measuring it is good practise to check the track has been correctly installed. Here are just some of the checks we recommend:
Check the track has been securely fixed
Ensure all straight joints and mitre joints have no visible gaps
Check that there are no visible gaps between the track and the surface to which the track is fixed (especially on the wall abutments)
Check for damage on the track (scratches, permanent marks and dents)
If there are T-Junctions, ensure the track has been correctly cut and the tracks go into each other rather than across each other
Above: First image show the glazing track incorrectly installed on a T-Junction, the second image is correctly installed with the tracks going into each other (this way the glass edges will meet)
In all the above cases, the issues are best resolved before the glass is installed. While waiting for the glass to be produced and delivered, it is recommended that the track is covered and protected with corex or a similar protective material to ensure the track does not get damaged.
Now-a-days, bottom track usually consists of 2 Part Track, one part is fixed into the ground surface (usually “L-Shaped”) and a second part that is used as a “clip-on” bead - clipped in once the glass panel is in place. With this method the glass panel will be tucked into the top track and rest on the bottom track. Once the panel is in place the bead is clipped in on the bottom track. Full height measurements need to take into account the depth of the pockets in the top and bottom track. It is a good idea to contact the track manufacturer to obtain details and measurements of the profile, especially the pocket area for accuracy. Also check the glazing track inserts or gaskets and glass packers that may need to be inserted in the bottom track. These items and others should be deducted off you full height measurements, giving you the glass panel heights.
Above: A basic example of a 1 part and a 2 part glazing floor track
If a solid bottom track (or one part track) and solid top track is being used, the glass will need to be installed using an “up and over” technique - lifting the panel fully into the top track pocket to go over the bottom track and then lowered into the bottom track pocket. For this method the full height should be measured and then the hight of the bottom track deducted. You may want to deduct further due to glass factory tolerances (to ensure the glass can be lifter over the bottom track while fully tucked into the top track). Glass packers can be placed inside the bottom track pocket to ensure glass panels have sufficient hight to stay inside the top track once they are lowered into position. Glass packers come in 1-6 mm thickness - it is important to ensure the glass panels sits securely inside the pockets before ordering the glass.
Measure the hight on several points to pick up any variances especially on longer the runs
Check the level of all surfaces
As with the glass panel heights, check the pockets depths of the wall abutments (and door legs) into which the glass will “slide”. As mentioned above, it is good idea to contact the glazing track manufacturer and obtain details of the profile, especially the U-Channel pockets. The types of glazing joints specified is another important consideration. In glass partitioning wet joints or silicone joints usually vary between 3-6mm in width. While partitioning dry joints (pre-formed plastic joints with a adhesive tape) usually require a 2-3mm gap. Sometimes special double sided glass partitioning tape may be specified.
Measure the widths on several points to pick up any variances
Check the level of all surfaces (including door legs) to ensure these are vertical
Once the width has been obtained, glazing inserts, pocket depths restrictions inside the glazing channel, etc should be deducted. Once the deductions have been made, the width measurement should be divided normally into equal parts. Glass panels are usually 700mm to 1,000mm wide and doors (depending on access, their use and building requirements) are usually 900mm wide. Glass panels next to doors or on T-Junctions tend to be narrow, and often referred to as glass rips. Establish number of joints on the opening width and deduct these measurements too.
Submitting Measurements for Production
We recommend having a detailed drawing of the area to be glazed. Each panel should be numbered on the drawing. When submitting measurements, each panel should be listed and numbered with their respective sizes (width x height) and specifications.
Additionally, a submission for production should also include:
Glass thickness (for example 10mm, 12mm, etc)
Details of glass panels that require cut outs (a notch in the glass usually to accommodate skirting, piping, etc.). Preferably include a diagram of the panel with measurements of the cut out
Details of raked glass panels (where a panel will be installed next to a slope, for example a 30 degree angled ceiling). Preferably include a diagram of the panel
Glass mitre joints (2 glass panels meet at an angle and the edges need to be angled, for example 2 glass panels forming a 90 degree corner may need to have a 45 degree edge to form the 90 degree corner)
Glass type specifications - such as laminate, acoustic, etc
Specify if you want only certain edges of your glass polished or if you would like these to be polished all round (often abbreviated as PAL)
Depending on the project other specifications may be needed - for example hinge cutouts details for glass doors, glass edge details, etc.
See first image.
Part 1 and 2 of this guide we have had a brief look at the step by step process to measuring for glass partitioning, this was done in 2 parts:
Measuring openings and site survey
Measuring glass for production and install
There are many considerations to take into account, but these are all vital to reduce costly errors. It is impossible to cover all aspects and considerations, such as measuring a curved glass screens, glass door details, glass T-Junctions, double glaze partitioning and more.
Each job will be unique and have its own complexities. As always we recommend using qualified experienced partitioning fitters to both measure and install your partitioning project. At Prism Glass we have over 10 years experience in the industry and have worked on many glass installation projects. If you need assistance with your project, please contact us and we will be more than happy to help.
Note: It is impossible to cover all aspects of measuring and site surveys in these articles and these articles should be viewed as a guide only. These are just some on the steps we usually take. Each project should be treated separately, as no project is the same.