In  September 2016, CHP hosted a window restoration workshop led by Bob Yapp, a world renowned preservationist. Mr. Yapp has been involved with preservation efforts for over fifty years including publishing numerous articles and books, working on restoration projects across the country, hosting the PBS program About Your House with Bob Yapp, and currently teaching hands-on preservation both at The Belvedere School in Hannibal, Mo, and in workshops across the country.

Twelve workshop attendees spent three days learning the art of restoring original wood windows at the Sweet House.


All sashes were removed and completely scraped to bare wood. Window jambs were scraped to bare wood also. Wobbly sashes were squared up and re-pinned. Severe damage was fixed with new wood or a Dutchman patch (bad wood is cut away and replaced with a patch of good wood).


The group planed and routed the sides of the sashes to accommodate “t-strip” metal weather-stripping. Additionally, rubber weather stripping was placed at the meeting faces of the sashes and at the top of the upper sash. This weather stripping has proven to eliminate nearly all drafts!


The group primed the sashes and jambs, installed the original panes of glass, and learned proper techniques to putty the window glass. The sashes were installed along with the new weather stripping.


Through their efforts, six windows in the Sweet House have been restored to their original state. and will last another 150 years.

For more information about Bob Yapp, and to learn why you should never replace wood windows with disposable replacement windows (one reason: replacement windows only last approximately 15 years!), go to:

Led by preservation experts Bob Yapp and Patrick Kennedy, CHP hosted a second window restoration workshop at the Sweet House in April 2018.

Guided by Bob and Pat’s 40 plus years of preservation experience, fifteen workshop attendees learned the art of restoring original wood windows.  Through their efforts, six more windows in the Sweet House have been restored to their original state  and will last another 150 years.


Bob shared with the group that approximately 32 million window sashes end up in landfills every year.  Up until ten years ago, almost all were old wood original windows.  Today, almost 1/3 of the throw-aways are less than 20 years old.  Bob cautions against buying into claims by window manufacturers that new windows are cost effective and energy efficient.  Many of these companies have been fined by the Federal Trade Commission for  making fraudulent claims of 30-60% energy savings.  The thing to know and remember is that glass is good for light and air flow but not thermal performance.  Interesting fact:  In rehabbing over 160 historic properties Bob has never replaced a window!


At the end of the workshop Bob Yapp said, “I’m really grateful to be around people who understand and care about what we are doing.  It does matter.  And preservation doesn’t cost, it pays you.”  CHP agrees!

Please note, you don’t have to live in a 150-year old house  to need window restoration.  Many younger homes have wood windows that can be restored!

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