DIY Network

Front Porch Facelift: Stamped Concrete A cracked and peeling concrete porch gets a whole new look with a stamped concrete overlay. From "Rock Solid" episode DROC-210

(Continued from page 1)

Stripping and Cleaning the Concrete

• This project must begin with a completely clean concrete surface. The overlay will chemically bond with the concrete. With this particular porch, it' s the old layer of paint that must be removed. Using a grinder with a diamond blade, grind in smooth circular movements until the concrete is the only thing left (figures B and C). Make sure you wear safety glasses and a mask to prevent inhalation of the paint dust.

  Rock Solid Tip: Hook the grinder up to a shop vacuum to keep the work less dusty (figure D).

  Figure B

  Figure C

  Figure D

  
  

  advertisement

  
  
  

• Once the top layer of concrete has been ground down, use a 3000 psi power washer to clean the newly exposed surface and get rid of dirt and debris. The goal is to remove dirt that an ordinary hose would not. Once done, double check that the concrete is thoroughly cleaned and that no paint remains (figure E).

• Power washing completely removes the layer of old paint (figure F).

  Figure G

  Figure E

  
  

  	Figure G
  	Figure H

• The next step is to etch the concrete with muriatic acid (figure G), then adjust the concrete' s pH with ammonia to ensure that the overlay properly bonds to the concrete. In a clean bucket, mix eight parts water to one part muriatic acid. The acid will etch the concrete, exfoliating it and opening its pores.

  Safety Alert: Muriatic acid is caustic and hazardous. Follow manufacturer's safety precautions and wear a mask and gloves during this process.

• In a separate bucket mix eight parts of water to one part ammonia.

• Flood the porch with your acid solution first. Spread it with a broom so everything is covered (figure H). Once the acid stops fizzing, flood the porch with the ammonia mixture to neutralize the acid and adjust the pH. The ammonia reacts immediately, so you do not have to wait to let it take effect.

• Use your power washer one more time to rinse excess acid and ammonia from your porch.
  

  Figure I

• Prep the house for the skim coat by taping the door jams and edges of the house with painters tape (figure I). This step ensures that the skim coat does not bond to the house.

• To mix your thin finish skim coat, take your mixing paddle and heavy duty mixing drill and place it in an empty five gallon bucket. Add seven to eight quarts of water to the bucket first, and then add a 55-lb bag of thin finish. Wear a mask. Mix it so that the consistency is very soupy, with no lumps. Let the material set for five minutes and then re-mix.
  

• Before applying the skim coat, make sure your concrete is wet, but with no puddles. Pour the skim coat out in sections and spread in U-shaped motions (figures J and K) with a squeegee. Start at the edge and work your way out. Spread the skim coat evenly and without lines. Use a paintbrush for the edges, since the squeegee is too big.

• The skim coat should dry for several hours (figure L) before beginning applying the next stamping coat.

  Figure J

  Figure K

  Figure L

  
  
  
  

  1 | 2 | 3 | 4

  
  
  

  RELATED PROJECTS: 1915 Row-House Restoration: Front Porch Repair 1909 Queen Anne Restoration: Balusters and Door Glass 1909 Queen Anne: Restoring Stone Balusters WEB-EXTRA: More on Cast Concrete and Molded Accents Concrete Flooring: Demolition Concrete Flooring: Preparation and Application Concrete Flooring: Applying Finish Concrete Flooring: Acid Staining Concrete Flooring

  
  

  ALSO IN THIS EPISODE:
  	Front Porch Facelift: Stamped Concrete