DIY Network

1909 Queen Anne: Restoring Stone Balusters From "Restoration Realities" episode DRTR-201

DIY's Restoration Realities visits Portland Oregon and the 1909 Queen Anne home belonging to Francene and Tim Grewe. This first of two restoration projects focuses on restoration of concrete porch balusters that have begun deteriorating after about a century of use and exposure to the elements.

The problem: missing and damaged stone-like balusters made of cast concrete.

The solution: replicate the balusters by creating a mold and casting new ones.

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	Our project house, a 1909 Queen Anne, has nearly a hundred cast-concrete balusters that are around a century old.
	The project: cast and create replacements for all of them.

Project 1: Restoring Stone Balusters

Materials:

existing baluster (the most intact concrete baluster available)
polyester filler
modeling clay
1/2" plywood
orange shellac
molding plaster
fiberglass cloth
1/2" plywood support strips
parting agent (mold soap or the equivalent wax)
baby powder or talc
denatured alcohol
concrete

Tools:

metal spatula or knife
3" putty knife
clay sculpting tools
assorted paint brushes (to apply shellac, parting liquid, and wet plaster)
jig saw (to cut plywood for fences)
glue gun (to fasten the fence parts together)
drill motor (for mixing plaster and for driving/removing screws)
screwdriver
hammer
rubber mallet
round file (coarse)
metal square
scooper
two 5-gallon plastic containers (mixing containers)

Estimated completion time:

• Two days to create the mold;
  
• Six hours to create each baluster;
  
• One hour to install each baluster.

Figure A

Creating a Model and Mold

The process of restoring the balusters is really one of replacing them with newly made replicas. The first step is to create a clean "model" for those replacements, then make a mold that will be used for pouring concrete into in order to make the replacement balusters that will be needed. Following are the basic steps in the process.

• Select the existing baluster that's in the best shape and remove it (figure A).
  

• Begin by restoring one side of the baluster to recreate the missing details. Use polyester filler to reshape the surfaces (figure B).

• Use modeling clay to finesse the details (figure C).

  Figure B

  Figure C

  
  

• Apply shellac to one baluster side (figure D).

• Install the fences at 45-degree angles to create a mold of that side. Seal the fence edges and baluster with modeling clay.

• Apply shellac to the fences (figure E)and clay and let dry.

  Figure D

  Figure E

  
  

• Apply molding plaster in a thin layer and let dry.

• Apply six to eight successive layers of molding plaster (figure F) and fiberglass.

• Glue support boards into the mold with the wet plaster and allow mold to harden.

• Remove the mold from the baluster and fences. This first mold is called a "plug mold" (figure G).

  Figure F

  Figure G

  
  

• Apply fences to the plug mold to make a container for wet molding plaster

• Pour in wet molding plaster into the mold (figure H) and allow to harden

• Remove the wooden fences (figure I) to reveal the plaster casting.

  Figure H

  Figure I

  
  

  This first casting is one side of our four-sided plaster baluster (figure J). Repeat the wet-plaster pour three more times to create the other three sides of the plaster baluster.

• Glue all four plaster sides together to create a complete baluster model (figure K).

• Finesse the corners with wet molding plaster and finesse any other details on this model.

  Figure J

  Figure K

  
  

  Figure L

• Using the restored baluster model, repeat the first fencing-up process and create four new plug molds. (It's possible to make two opposing sides at the same time)

• Check the new plug molds. Finesse as needed and make sure the corners fit perfectly.

• Coat the new plug molds with shellac and let dry

• Wax down the sides of this new mold and assemble all four sides to create the final baluster-mold (figure L).

  Note: Once you have the final baluster mold, you may discard the final baluster model since the model's only purpose was to create a clean and perfect mold.
  

  	Figure M
  	Figure N

Now that the process of creating a mold is finally complete, the process of actually pouring the concete to create the replacement balusters can begin. Compared to the multistep process of creating a model and mold, this part of the project is straightforward. Of course the time it takes will depend on how many pieces you have to cast. In the case of our project house, casting the first baluster was just the beginning of a long, arduous job.

• To create the first baluster, wax down the inner surface of the mold so that the concrete won't stick to the mold. Close off the bottom of the mold with a waxed plywood board.

• Pour a medium-wet mix of concrete into the mold.

• Allow the concrete to harden.

• Disassemble the four sides of mold (figure M) and reveal the first concrete baluster (figure N).
  

  	Figure O
  	The old and the new: a century-old concrete baluster and its newly made replica.

• Let concrete cure overnight. Finesse corners and gaps with similar mix of wet concrete.

• To make multiple balusters, simply repeat the process as often as necessary: clean the mold, re-wax it, and pour in fresh concrete. For the project house, this process was repeated 99 more times to replace all 100 original balusters!

• Re-install the balusters where the missing ones were (figure O). Apply mortar to the tops and bottoms of each and tool the joints.

RESOURCES :

Renovating Old Houses: Bringing New Life to Vintage Homes
Author: George Nash
Publisher: Taunton Press
ISBN: 1561585351
Order this title from Amazon.com.

Renovating and Restyling Older Homes: The Professional's Guide to Maximum Value Remodeling
Author: Lawrence Dworin
Publisher: Craftsman Book Company
ISBN: 1572180293
Order this title from Amazon.com.

Selecting and Renovating an Old House: A Complete Guide
Author: United States Department of Agriculture
July 2000
Publisher: Dover Publications
ISBN: 0486409562
Order this title from Amazon.com.

Architectural Reproductions Inc.
Website: www.archrepro.com