Porch Columns - wood problem
Post new topic   Reply to topic
Historic HomeWorks Forum Forum Index -> All Other  
View previous topic :: View next topic  
Author Message
puppychew



Joined: 27 May 2010
Posts: 17

PostPosted: Mon May 09, 2011 9:02 pm    Post subject: Porch Columns - wood problem Reply with quote

Hi - I am stripping my porch columns. Aside from the usual problems, there is a section where the wood seems like it is peeling.

The paint was removed with a heat gun and came off easily. The wood underneath was not gouged by the scraper, but appears as if it was. There are 6 inch long and about 1 to 1/2 inch wide layers of wood that look as if they can be peeled off. Under that, there are more thin layers.

Columns are hollow, one piece.

What is the cause and what can I do to fix this?

thanks!
Back to top
View user's profile Send private message
johnleeke
Site Admin


Joined: 20 Aug 2004
Posts: 2924
Location: Portland, Maine, USA

PostPosted: Wed May 11, 2011 6:38 am    Post subject: Reply with quote

If you actually have one-piece hollow bored-center column shafts, it sounds like the wood is delaminating along the annual growth rings.

To understand the cause and come up with a fix, we need to know a little more. Can you attach some digital photos to your next message and show us what it looks like?

Where on the columns is this happening? The shaft? The base? The plinth?

Go here:
http://www.historichomeworks.com/hhw/reports/reports.htm#Columns

and view the sample pages of the


Practical Restoration Report on Columns,

to learn the basics of column construction.

_________________
John

by hammer and hand great works do stand
by pen and thought best words are wrought
Back to top
View user's profile Send private message Send e-mail Visit poster's website
puppychew



Joined: 27 May 2010
Posts: 17

PostPosted: Wed May 11, 2011 7:40 am    Post subject: Reply with quote

Attached is a photo.

It is located on the shaft of the column facing East.

There is a crack from the plyth that extends upward about 7 inches. This is where the photo was taken.

The delaminating begins about 2 inches from the bottom of the shaft and continues about 4 feet up.

This column has a solid base and is not vented (yet).

So far I have sanded and applied a consolidant.



IMG_6427.JPG
 Description:
 Filesize:  277.11 KB
 Viewed:  141 Time(s)

IMG_6427.JPG


Back to top
View user's profile Send private message
puppychew



Joined: 27 May 2010
Posts: 17

PostPosted: Wed May 11, 2011 9:33 am    Post subject: Reply with quote

also
Drilling a vent hole and the wood seems very thick.

The circumference is 24 inches, therefore if I did this right the diameter is about 7.5 inches.

When I insert a wire into the hole I drilled, it extends about 5.25 inches. That leaves 2.25 inch thick wood. Only about 3 inches of space to vent. (this is near the base of the shaft)
Back to top
View user's profile Send private message
johnleeke
Site Admin


Joined: 20 Aug 2004
Posts: 2924
Location: Portland, Maine, USA

PostPosted: Wed May 11, 2011 10:42 am    Post subject: Reply with quote

That does look like annual growth ring delamination. It's not common, but does appear in shafts that are turned from a solid, full round, log. This is usually a form of deterioration that is in the wood itself, and was probably there since the column was first made. The root cause, then, is probably poor wood selection during the making of the column shaft.

When you drilled the vent hole, were there any signs (on the wall of the hole) that indicated delamination? Was the hole through an area of delamination? If so, how deep from the outer surface did the delaminations seem to go?

What epoxy methods, materials and products have you been using? How is the weather there? (temperature, damp or dry, etc.)

Can you post a photo showing the overall situation (porch deck, the whole column, roof above, etc. Another detail showing the whole crack would help. The delamination and the crack will probably need different repair methods.

Also, where are you located, and how old is the house & column?

_________________
John

by hammer and hand great works do stand
by pen and thought best words are wrought
Back to top
View user's profile Send private message Send e-mail Visit poster's website
puppychew



Joined: 27 May 2010
Posts: 17

PostPosted: Wed May 11, 2011 12:25 pm    Post subject: Reply with quote

The vent hole is not completely drilled yet - need to buy a new bit.

Sawdust that came out was a mud color and texture - not black nor like new wood.

House is in PA and built in 1905. There is no water infiltration from above. Column is in part shade.

The delamination is only about 6 in wide and 4 ft tall. I applied Abatron consolidant to the area.

There are lots of cracks in all columns like that, I was going to caulk the cracks. Someone installed glazing putty in the cracks at one time.



IMG_6430.JPG
 Description:
 Filesize:  72.04 KB
 Viewed:  137 Time(s)

IMG_6430.JPG



IMG_6430.JPG
 Description:
 Filesize:  72.04 KB
 Viewed:  118 Time(s)

IMG_6430.JPG


Back to top
View user's profile Send private message
puppychew



Joined: 27 May 2010
Posts: 17

PostPosted: Wed May 11, 2011 12:26 pm    Post subject: Reply with quote

another pic


IMG_6432.JPG
 Description:
 Filesize:  66.81 KB
 Viewed:  130 Time(s)

IMG_6432.JPG


Back to top
View user's profile Send private message
johnleeke
Site Admin


Joined: 20 Aug 2004
Posts: 2924
Location: Portland, Maine, USA

PostPosted: Wed May 11, 2011 1:29 pm    Post subject: Reply with quote

OK, now you've three things going on: Delamination, Cracks, and Vent Hole.

To prepare the repair areas, remove all the paint down to bare wood and back one or two inches from the repair. (Work Lead-Safe!)

Delamination

Remove loose layers of wood. Use a sharp knife or chisel to cut away sections that are loose and open on two or three sides. Cut through the layer vertical to the surface, but do not cut into the layer beneath. It's OK to leave sections of layers that are loose on one edge, but still well attached to it's own layer on the other three edges. Leave your cut edges perpendicular to the surface, do not feather them out by trimming with the knife or chisel and do not sand them out to a feather edge.

Drill 3/16" diameter holes on a grid of 1" x 1", over the area of loose delaminations. To determine the extent of delamination, tap the surface with you finger nail, or thump it with your finger and thumb, or tap it with the wooden handle of a light tool, and compare the sound with taping where the wood is not delaminated. A hollow, papery sound indicates delamination. Sloping the holes down at about 45 degrees. As you drill the holes, hold the drill lightly and see if you can feel the space between the layers. Drill the holes as deep as the delamination, but not all the way through the wall of the shaft.

Apply epoxy consolidant
into the holes and along the loose edges of the delaminated layers. Do this neatly with a narrow-spouted plastic bottle, and work the consolidant in under the delaminations with a thin metal pallet knife. The consolidant with seep between the loose layers. Go back and apply more consolidant to the edges and holes every 10 or 20 minutes until no more soaks in after 30 minutes.

Do NOT brush consolidant over the entire surface of the repair area. This will trap moisture in the repair area leading to rotten wood over the long term.

Now, only in the areas that are lower than the original shaft surface, brush on one application of consolidant. Let it soak in for 30 minutes and then wipe off any remaining. Let the consolidate cure until it is about 80% cured. First the surface is wet, then sticky, then tacky. A short time after the surface is tacky it is ready for the next step, filling.

Fill the voids of missing wood, With epoxy paste filler. If there are any loose layers, work a mixture of 50% paste filler and 50% consolidant between the loose layers with a putty knife. (Both the consolidant and filler have to be pre-mixed from their A Part and B Part.) This 50% paste and 50% consolidant mix acts as an effective gap-filling adhesive. Wipe off any remaining mix from the surrounding surfaces and then apply the regular epoxy paste filler to fill in the voids of missing wood, and to fill the holes. Slightly over-fill the voids, then let the epoxy cure for a couple of days.

Trim down the cured epoxy to be flush with the surrounding wood. This may be tricky because the surface is curved in one plane, and may even be curved in two planes. If you trim off too much, you can always fill again and re-trim.

Vent Holes

Drill the vent holes.

Give the inner walls of the holes an epoxy consolidant treatment. (This keeps the hole from being a source of moisture that could lead to fungal decay of the shaft around the hole.) The consolidant with seep more into the end-grain. Go back and apply more consolidant to the end-grain at the bottom of the sides of the holes every 10 or 20 minutes until no more soaks in after 30 minutes. Wipe off any remaining consolidate and allow to cure for 10 to 15 days before putting a metal vent or screen into the hold. (Allowing the long cure time helps prevents permanently gluing the vent into the hole.)

Cracks

Clean out all the the old paint, putty and junk, so the interior sides of the cracks are bare clean wood.

Prime the interior sides of the cracks with the same paint primer you will use to paint over the repairs.

Apply a compressible foam backer-rod to cracks that are wider than 1/8". Set the surface of the backer-rod so it as deep from the column shaft surface as the crack is wide.

Fill the cracks with a paintable high-performance (at least 100% elongation rating) sealant, and tool down to the surrounding surface. (I often use Sonneborn's NP1 sealant, but others may be good too.)

Sand or trim all epoxy surfaces to remove any tacky amine blush that can cause paint failure. Protect all repair areas with an effective paint coating system, such as oil-based alkyd resin primer, and two top coats of 100% acrylic house paint that costs $35-50 per gallon.

Try out each of these methods complete first, before proceeding to additional repairs. If you bump into any problems on your first go, come back for more suggestions.

If you use any of these ideas, please post some photos of you doing it, and your final results.

_________________
John

by hammer and hand great works do stand
by pen and thought best words are wrought
Back to top
View user's profile Send private message Send e-mail Visit poster's website
puppychew



Joined: 27 May 2010
Posts: 17

PostPosted: Wed May 11, 2011 2:01 pm    Post subject: Reply with quote

Thanks John - I will keep you posted.

Confused about the consolidant - I thought you could apply it almost like a paint to strengthen the wood. I already applied it to the entire end grain sections and many other areas.

Also, the 2 inch vents I have are another project finding a drill bit that size that will go that deep. Already went to 2 stores with no luck.

Thanks for your help!
Dan
Back to top
View user's profile Send private message
johnleeke
Site Admin


Joined: 20 Aug 2004
Posts: 2924
Location: Portland, Maine, USA

PostPosted: Wed May 11, 2011 3:02 pm    Post subject: Reply with quote

Quote:
I'm confused about the consolidant - I thought you could apply it almost like a paint to strengthen the wood.


When using epoxy it is better to think: Less is More

Effective wood-epoxy repairs are possible when you pay more attention to the wood and less attention to the epoxy. There is nothing magic about the epoxy product, success comes entirely from having a good repair design and use good methods implementing the design.

Consider carefully whether or not the wood needs to be "strengthened." Wood "strengthened" with epoxy is not always better. Often the wood is strong enough to do what needs to be done. In many cases we want the wood to be "weak" in certain ways. For example, the surface of the wood needs to be "weak" enough to let water vapor pass out of the wood, helping it to keep dry. Moisture vapor will migrate from the inner volume of the wood to the outer surface, right through the paint coatings, and out into the air. If the surface of the wood is "strengthened" with an epoxy plastic coating, then the water is trapped in the wood--not good.

Mother nature has done a fabulous job of designing and producing the wood. There is little we can do to it to make an improvement. In fact, the things we do to it sometimes end up damaging the wood.

Epoxy materials can be used as a pre-treatment before painting a sound wood surface, but Abatron's LiquidWood consolidant is not the best product for that use. In fact, even with the products designed for this use, the potential for trapping moisture in the wood is increased, along with the risk of excessive moisture and fungal decay.

_________________
John

by hammer and hand great works do stand
by pen and thought best words are wrought
Back to top
View user's profile Send private message Send e-mail Visit poster's website
puppychew



Joined: 27 May 2010
Posts: 17

PostPosted: Thu May 12, 2011 1:54 pm    Post subject: Reply with quote

Ready to give up on venting.

I spent a few hours drilling and chiseling and only 1 inch into the column. Columns walls are 2 1/2 in thick with only about 2 1/2 inches hollowed center.

My vents are 2 in wide. Louvers w screens. Maybe if I don't seal all the cracks, that will vent it enough? Should I just drill a 1 inch hole and glue a screen to it?
Back to top
View user's profile Send private message
puppychew



Joined: 27 May 2010
Posts: 17

PostPosted: Thu May 12, 2011 8:14 pm    Post subject: Reply with quote

Actually the more I read I am thinking that it's probably ok that I am not able to vent the columns with the 2 inch vents. There is only about 2 1/2 inches of air space in there anyway.

Since the cracks were created to allow the columns to vent. if I try just drilling a 1 inch hole and inserting a screen and there is not enough ventilation, the columns will just produce new cracks.

My thought is to drill a 1 inch hole (top and bottom), glue a screen in somehow, and caulk only a few of the cracks. Not sure if it's better to caulk the larger or smaller cracks.

Keeping the cracks will not look that great, but I will be sure the columns will be stable and get the necessary ventilation.

Does this make sense?
Back to top
View user's profile Send private message
johnleeke
Site Admin


Joined: 20 Aug 2004
Posts: 2924
Location: Portland, Maine, USA

PostPosted: Fri May 13, 2011 8:23 am    Post subject: Reply with quote

Caulk all the cracks, this will help keep liquid water out of the columns.

A 1" hole, top & bottom, is better that no ventilation.

Screen
Form the screen into a cylinder, so it is a "friction fit" in the hole and does not need to be attached or glued. This will make it easier to take out the screen when future maintenance is needed.

To form the screen, drill the same size hole in a scrap of wood. Lay the scrap flat on the bench. Cut a round piece of screen about 1" larger in radius than the hole. Lay the piece of screen over the hole. Take a piece of round dowel about 1/8" diameter smaller than the hole, and press the screen into the hole. Tap the dowel lightly with a hammer so the screen is pressed into the hole, until the screen and the end of the dowel are against the bench. Pick up the piece of wood, screen and dowel, and push the dowel and screen on through the hole. The screen will be formed into a cylinder, with one open end.

Carefully tuck the screen-cylinder into the hole in the column shaft. It will tend to stay in place by friction.

_________________
John

by hammer and hand great works do stand
by pen and thought best words are wrought
Back to top
View user's profile Send private message Send e-mail Visit poster's website
johnleeke
Site Admin


Joined: 20 Aug 2004
Posts: 2924
Location: Portland, Maine, USA

PostPosted: Fri Jul 20, 2012 10:18 am    Post subject: Reply with quote

How did you make out on your column repairs last year? Any photos?
_________________
John

by hammer and hand great works do stand
by pen and thought best words are wrought
Back to top
View user's profile Send private message Send e-mail Visit poster's website
Display posts from previous:   
Historic HomeWorks Forum Forum Index -> All Other  
Post new topic   Reply to topic All times are GMT - 5 Hours
Page 1 of 1

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
You cannot attach files in this forum
You can download files in this forum