There are many factors to consider when writing formliner into an architectural concrete project specification; the wrong pattern, a substandard formliner or poor finishing techniques can negatively affect the aesthetic. This makes the project specification, and how it is written, vital in ensuring that the completed project matches the original design.
Here we’re highlighting just a few key components to assist you in writing a clear and detailed specification for your architectural concrete formliner project so that the end result matches your design vision.
Once you’ve zeroed-in on the formliner pattern for your design, the best way to ensure that your requirements are met is to not only list the preferred formliner manufacturer but also the pattern name, pattern number, range of rock size – if it is a rock or stone pattern – depth of the relief and grout width as well as including the note, “or equivalent.” Adding the option for an equivalent will allow the contractor to find the most cost effective option when it comes time to purchase formliner while also making sure that the formliner pattern meets each of your above requirements.
In the case of natural stone you may also want to require that the pattern be one that was cast from a vertical application that was made from real stone, rock or brick. Doing so means the pattern of the liner will be varied and the texture of your design will reflect the innumerable and interesting textures of natural stone.
Specifying a high reuse urethane formliner is the ideal choice for an architectural concrete project, especially if your design includes a rock or stone pattern with a natural appearance, or if you are creating an intricate custom mural or graphic. Urethane formliner lends itself to very precise details, edges and the varied features of natural textures.
However, solid urethane is not always the best option for a project budget so most manufacturers – including Custom Rock – produce their patterns in several grades and materials, which lets contractors choose a pattern that fits their budget and the necessary number of reuses while still staying within the parameters of the design specification. This is another instance where including the “or equivalent” note in your specification is helpful.
All poured vertical texture applications will need some finish work. Seams between liners and holes made by attachment anchors mean that finishing will be essential, the quality of which is extremely important.
Be as detailed as possible in writing the finishing portion of your specification. For example, specifying that the joints and holes be patched and hand shaped to meet adjacent surfaces and blend in or match the character of the texture. You will also want to require that the seam lines and other protrusions be ground down so that they also match the chosen texture.
One way to minimize the amount of finishing that will need to be done is to choose a liner that is keyed. Keyed formliners are cut along the grout joint between stones so that they fit together like a puzzle piece rather than aligning in the middle of one of the stones which requires more finishing – hand-blending and grinding – once the concrete has cured.
Writing submittal requirements into your specification is the best way to make sure the formliner pattern and the contractor’s work meet your standards.
Submittals can be as simple as a pattern cut sheet or small formliner sample, but requiring that the contractor deliver a poured sample panel using the specified pattern, or the chosen equivalent, will allow you to see how the finished application will look while also giving you the opportunity to see the quality of the contractor’s work, both of which will guarantee you’re happy with the end result.
In addition to the things we’ve discussed here there are further considerations when writing your specification and we are happy to help you should you have any questions or need any assistance. You can contact us by phone at 800-637-2447 or by filling out the form on our Contact page.
If you would rather, our website is also a great resource for information; all of our patterns have a spec sheet with detailed information. On the Resources page you can learn about our different formliner grades, request a CAD file for any of our patterns or download a detailed sample specification to help you when writing your own.
Thank you for your interest in Custom Rock and for designing your project with architectural formliner.