Yet there are a number of temporary methods that help you attach—and later remove—those pictures, framed prints, cards, and posters. Plus, there are a few permanent ways to help you attach heavier items like shelves with relative ease. Mounting putty is especially good for cinder block walls, because it is thick enough to fill in cinder block’s bumpy surface. It’s best for light-weight items up to an ounce or two like cards, posters, photos, and drawings. Because it can be mounded up, it can even hold light-weight decorative objects like coins or keys. Mounting putty can be removed, leaving behind little to no oily residue. It can be reused a number of times. Hardwall hangers have weight limits ranging from six to 25 pounds and are best for items such as coats, umbrellas, mirrors, and large framed pictures. Hardwall hangers are used only for hanging items and cannot be used to mount a shelf. Hardwall hangers are semi-permanent. So, with a claw hammer, it’s easy to pull out the plastic hook. Because the pins have no heads, the hook will pull straight out, leaving the pins behind. Removing the pins can take some effort, but if you manage to do so, you’re left with only a few small holes that can be patched over. Though glue guns are most often used for hobbies and crafts, many users swear by them for sticking things to cinder blocks. Since hot glue warps paper, it’s best for sticking solid objects to cinder block rather than posters and pictures. Curing time is fast: just a couple of minutes. The holding capacity of hot glue on the cinder block is only a few ounces. For extra holding capacity, look for construction-grade hot melt glue sticks. If you go that route, you’ll also need to purchase a high-temperature hot melt gun. The thin foam backing helps the hooks stick to the cinder block. Most self-adhesive hooks are meant for light-weight items only, but some are rated up to five pounds for things like large framed canvas pictures. Be sure to clean the cinder block with rubbing alcohol first for maximum adhesion. Landscape block adhesive is a paste-like heavy-duty exterior adhesive used for things like attaching block caps to retaining walls. But it can be used whenever you need a reliable cinder block adhesive. Use landscape block adhesive for permanently attaching medium-weight items like shelves that are no more than 50 pounds. Use landscape adhesive judiciously and only for permanent additions to the cinder block. That’s because landscape adhesive is difficult to remove from the wall. Even if you do manage to pry off the item, you’re left with cured, hardened adhesive residue that’s nearly impossible to remove. Light-weight concrete screws 3/16 inch in diameter and one inch long have a shear (or breaking) strength rating of 720 pounds. It’s important to remember that these ratings apply only to the screws, not to the item being mounted or to the cinder block. But it’s safe to say that correctly-installed concrete screws in cinder block will be strong enough to hold up shelves or a small floating writing desk. Since cinder blocks are hollow inside, they are an ideal match for expansion bolts. The bolt must be at least two inches long to clear the cinder block’s outer wall and reach the inner cavity. Once the bolt is in place, it is extremely strong, and it’s capable of holding up shelves packed with heavy items. Display strips come in rolls 1-1/2 inches wide by 12 feet long. The adhesive is activated by a water mist. When the adhesive loses its stickiness, it’s easily rejuvenated by an additional spritz of water. Display strips stick to cinder block walls, and things stick to the display strips: artwork, drawings, photos, maps, school schedules. Made of lightweight fabric, display strips are removable and can be moved to another location. Because display strips are non-marking, they leave the previous surface in perfect condition.
