Cedar is a natural decay resistant wood just like teak. But all things will deteriorate over time. First I would ask where are you located. This will determine the weather effects on the wood. Here it Texas lots of houses have cedar shingles, a really stupid thing to do- put dry wood on a house-other places call that kindling. The roofs usually last about 10-15 years untreated, depending on the particular piece. 10-20% will have to be replaced over that time due to warping. SOOOOO If you live in the non southwest desert local, where the dry sun beaten weather really kills wood, I would say not to seal it. If you are going to seal it use an oil not a polyurethane. The oil will polymerize and can be added to later.


Dave

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1970 220D, owned 1980-1990
1980 240D, owned 1990-1992
1982 300TD, owned 1992-1993
1986 300SDL, owned 1993-2004
1999 E300, owned 1999-2003
1982 300TD, 213,880mi, owned since Nov 18, 1991- Aug 4, 2010 SOLD
1988 560SL, 100,000mi, owned since 1995
1965 Mustang Fastback Mileage Unknown(My sons)
1983 240D, 176,000mi (My daughers) owned since 2004
2007 Honda Accord EX-L I4 auto, the new daily driver
1985 300D 264,000mi Son's new daily driver.(sold)
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