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Exterior Building Signs & Numbers goes to the birds? falling apart?

Posted by Frank Murch | Oct 29, 2015 9:50:00 PM

Exterior Building Sign Address Numbers goes to the birds? falling apart?

Signs for San Diego replaces address numbers on commercial buildings all the time.  Why we need to do this? Birds!!  Birds are destroying Exterior Building Signs like your Address Numbers. It is a problem with materials. We can help you make a better choice.Foam Letters

In the 1980s foam letters and numbers started to become popular. A lot of this has to do with material costs and a way of shaping these with a “hot wire”. 4 types of plastic expanded foam materials are common for Exterior Building Signs or Address numbers. Two types of foam have a couple fatal flaws:

Birds use foam to claw and peak. They love this.
UV (Ultra Violet radiation) resistance is not good, degrading your address numbers.


Birds don’t normally eat foam, there is no nutritional value to them. They are pecking and clawing your numbers for fun. Birds perch on the top parts and in the centers of the “0”s, “4”s,  “6”s, “8”s and “9”s in. In most all cases, the upward facing edges are where the deterioration starts. The letter is pulled apart from claws, and becks. The sun attacks the foam. The paint on the letter thins, cracks and birds peck at weak areas and exposing the foam. When the protective layer is penetrated, birds enjoy picking the edge of the paint layer completely off. Holes can be repaired with a polyurethane caulking. If you can see the damage, but birds peck at the top of the letter where is impossible to see. Birds do not like stucco and a thick coating of stucco keeps the birds away.Foam numbers

UV Deterioration

On the south side an Exterior Building Sign like an address number is in the sun all day long.  The numbers on the south side have maximum exposure to Ultra Violet light. Normally the damage will be worse on the south side, but the east, west and north facing sides still have bird damage and take longer. The UV breaks down the foam and in extreme cases a laminated face of a number falls off. Paint with a UV inhibitor, Dark colors such as  black, dark brown, dark reds, and blues resist UV deterioration much more effectively than lighter colors such as yellows, whites, light blues, and grays.

In the 1980s and peaking in the early 2000s foam were commonly available. Foam is cheaper, easier to shape and all the rage, but not all foams are created equal:

Gatorfoam board (Expanded Styrofoam and polystyrene) –this comes in a wide verity of brands, and it was very common. These look great – for a while. It is a bad choice because birds and the sun will destroy these over time. Unfortunately, many commercial buildings have this material in their Exterior Building Signs – their address numbers. It is a particularly bad material. Birds love it, it is a weak material and it is UV susceptible. On the positive side, it is cheap, but the cost difference is not dramatic

Dynofoam (Polyurethane) This is a rigid inflexible material. It is structurally good, but birds love it, they love to claw it, peck at it quickly and with a lot of interest.

Precision Board and Precision Board Plus (HDU High Density Urethane) is expensive and rarely used for address numbers. It is a great Exterior Building Sign material, but it is normally used for sand blasted signs. It is water proof, solvent resistant, structurally good. Insects, rot and birds are not a problem. Birds do not seem to like it. It is light weight and is expensive compared to other materials. Good choice, but not the best choiceFoam Letters

PVC, Sintra, Komax (Expanded Poly Vinyl Chloride) Birds do not like it. It is common for yard sprinkler systems. It is denser, stronger and more durable than the other foam materials. It is easy to cut into letters and can be painted. The sun’s UV dries it out over time and heat can warp it. It comes white and black.  It is matte finish if not painted. If it is thicker it resists warping.

Plexiglas (Acrylic) Birds can not get through it and they do not like it. It is heavy, dense and durable. It can be cut into numbers and painted. UV fads the color and the nice reflective surface dulls over the years. It expanded and contracts a lot from night to day, winter to summer so larger numbers can work loose. It is available in many colors, but white, and black are cheaper than colors. Some colors can be 2X the cost.

 Are your building address numbers going to the birds and falling apart? At Signs for San Diego, we make numbers to replace foam numbers.  We can replace numbers of one building or an entire industrial or retail complex. We like PVC or Acrylic, it does not rot, termites don’t like them, birds can not destroy them. They still fad in the sun, but they remain in good shape for years, Need new numbers?  We use a bucket truck to drive up, replace the bad numbers with good ones and solve the problem. Please give is a call for pricing and availability.

Contact us for a consultation  

Signs for San Diego specializes in Exterior building signage Oceanside, Exterior building signage Carlsbad, Exterior building signage Vista, Exterior building signage San Marcos, Architectural signage Oceanside, Architectural signage Carlsbad, Architectural signage Vista, Architectural signage San Marcos, Exterior Building Signs Vista Ca, Exterior Building Signs Carlsbad ca, Exterior Building Signs Oceanside ca, Exterior Building Signs San Marcos ca, Exterior Building Signs escondido ca, Exterior Building Signs poway ca, foam signs, exterior building signs carlsbad ca






Whether you need a channel letter set, a monument signs, ADA signs, wayfinding signs, lobby signs, or any other type of commercial building signage, we can help! Signs for San Diego is the best sign company for building signs.


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