STUCCO NEWS.NET

Good morning Sir,

WOW! I have learned so much from your site already this morning!

Here is my situation. I am in the process of purchasing a 3,200 sf stucco on wood lath home built in 1924 in York, PA (approx. 1 hour north of Baltimore, MD). I have seen multiple areas on the house where significant bubbling under the outer layer of stucco has occurred. On the garage, there are two spots(approx. 3 sq. ft each) where the lath is showing and the plaster has fallen from the wall. The home has been patched numerous times with numerous uneven patches(it seems to be pebble dash) and is really starting to show the uneven patching that has occurred, plus its been painted over several years which is making it even worse.

Here's my question please. A reputable contractor in the area (from what folks have told me) has recommended I consider having the approx 500 sf. areas that need to be fixed, fixed with appropriate grade portland cement and then having wood lathe fastened to the outside through the existing plaster walls, Tyvek over the whole exterior, and apply either vinyl (yuk) or better yet go with the newer cement board(like HardiPlank).

I am neutral minded to the idea, in part because of the cost of removing the existing stucco. Also suggested was removing the bad areas, having the painted over stucco cleaned of its paint, and stucco over the entire house.

Not sure what is best here, please help! I can provide pictures if this would help

You just can't put good over bad. I can tell you what is going on here:

The old stucco on wood lath isn't Portland cement, but lime and sand, and the pebble dash is lime and gravel. I have only seen Portland cement stucco over wood lath once in my life. It was a house built in the 1920's in Takoma Park, Maryland. Since metal lath came out after the turn of the century, most stucco including lime and sand was put on metal lath. Portland cement took over all stucco about 1930, and wood lath disappeared.

The bulges and loose stucco are probably lime and sand that has dissolved, sometimes from a leak above, or just old age. The quantity of patches on the house indicate there was other stucco failure. The failure could have been caused by leaks, just deterioration due to old age, or failure of mortar to key well into the wood lath or broken keys.

For whatever reason, the stucco should be removed. Patching up a patched up mess will always look like a patched up mess. Wood lath was never really worth a damn. Besides warping and broken keys, wood lath is a fire hazard. If removing the lath creates a problem with too much space to fill, some of the lath strips can be put on the wall vertically for furring.

The old stucco shouldn't be way too much to remove. Some of the patches may be hard, but can be broken off.

We sometimes re coat old stucco with our chipping and bonding method, but the stucco has to be really hard-like Portland cement over block or metal lath. I would never re coat old stucco that has wood lath or crumbly lime and sand. You just can't put good over bad.

By tearing off the stucco, you can assure a good water barrier like tar paper, but most importantly, new flashing behind the stucco and over the substrate. Most stucco failure and rot comes from bad or non existent flashing. I ought to know after fixing stucco for years and years. Also tearing off the stucco back to the old substrate assures securely nailing or fastening the new lath, (or maybe siding (yuk)). The last thing you want is repairs in the future.

The idea of securing the wood lath from inside the house sounds absurd if not impossible. Bear in mind any other material wood need furring, that is the framing straightened before nailing. Stucco doesn't need straight framing because it is a liquid material. You'll usually find crooked framing under most old stucco, because the wall was straightened with mortar.

Like I always say, when in doubt, tear it out.

Thanks so much for visiting my site.