Many people like you, who want an affordable home in the tropics, have asked questions about concrete walls but also wonder about drywall systems…are they safe? Are they strong enough to resist high impact loads, rain, sun and moisture?
Let me tell you that the answer is yes: the use of drywalls with plasterboards or fiber cement boards as internal and sometimes external walls, is gaining popularity among private residential projects. If used correctly it can provide a risk free solid construction.
These kind of products have improved a lot with the years, meeting high level specifications in the areas of acoustic insulation, thermal insulation and resistance to fire and damp conditions. Not only this, but aesthetically speaking, it is a versatile product that you can finish as you wish, or even, sometimes with no finish ( for those who feel sustainable) they look great!
There are many kinds and brands of drywall systems, imported and produced here in Costa Rica. It depends on what your budget can buy. It is recommended to go for something that’s in between, not too cheap, not too expensive. Sometimes a cheap gypsum board ( 2 carton faces, plaster with no additives in between) can increase your budget on adhesives, sealants, protectors, and general finishes due to it’s poor quality.
Products used in this tropical modern architectural project are following what is mentioned above. Speaking about external walls, we used fiber cement boards. These light panels made out of cement gives seismic resistance to our walls, the opportunity to save on finishes, since it comes ready to install. Resistant to moisture, fire,fungi and pests, it comes with an inside moisture barrier. There are many possibilities of installation and finishes, we sticked with groove and tongue installation both vertically and horizontally on the different modules of the house.
In areas where moisture problems may appear, we used mold resistant panels. We call it here “ lamina verde”. There are many specialties for this one, like underlayments, tile backerboards (fiber rock aquatough, sheetrock), ceiling panels, soffits , shaft walls and interior wall panels. Our “ lamina verde is located on interior second floor ceilings and bathroom’s interior walls.
We used Dens glass for exterior eaves finish and bathrooms ceilings. Dens glass combines glass fiber as surface with a core of silicone treated gypsum. It’s alkali resistant surface has excellent resistance to moisture. Strength, stability and fire resistance are the main features of this product. You cannot plate it, but you can finish it with mortars and paint colors. Great for exterior applications that need protection!
Duroc is a fiber cement board commonly used in exteriors or interiors. You can plate it and is very resistant since it will never disintegrate. This one is for more heavy duty areas too, and where humidity is going to attack. We used it on window sills, and some interior partitions exposed to an interior garden.
Some design considerations and good practices you have to take care when you are using drywall, is for example not touching the earth directly with the selected material. Try to elevate the house from the ground so this way the mold won’t come up.
Also when two different materials meet, try to separate them, so that way you won’t have cracks and air inlets. You can solve this using silicon rubber with a matching color, or locating a small glass or metal slot as a separator. This last architectural solution just looks great and gives a contemporary feeling to your residence.
When using drywall as a ceiling, make sure you are using different levels for the roof structure and the ceiling. If you pull the ceiling backwards, and bring the roof structure forward, you’ll make sure that all rain drops will not reach your drywall ceiling.
Make sure your eaves protect at least some part of your walls from direct rain and sun incidence. That you way the materials used on external walls will last longer time.
There are also many ways of protecting your drywall system from stretching and expanding, rain, excessive sun, humidity, insects. Many of you worry about moisture. Moisture can appear due to water leaks, poor roofing, poor exterior flashing installation, poor site drainage and bad plumbing. But not because of a drywall system. There is a wide variety of quality products that can help drywall systems last longer and improve their resistance to sun , rain and moisture incidence. But that’s our next topic! Until next time!