Installing Glue Down Hardwood Floors On Concrete - Page 1

Gluing of hardwood floors represents a sizeable part of the hardwood flooring business with most of it installed on concrete in homes that are generally on grade (no basement).

Not For The Timid DIY

These types of installations are more prone to failure Laying hardwood into adhesiveover all others. Some of the more common reasons include; improper or no floor preparation, wrong adhesives or incorrect amounts applied resulting in de-bonding of the material from the subfloor. This is why any glue down installation should be performed by someone that has the experience and know how. Adding to the difficulty is the mess involved.

How Are They Installed?

Gluedowns are installed by trowel spreading of adhesive on the subfloor in a pre determined area (shown above). Usually professionals will measure out three feet or enough for twelve rows to cover, using a three inch wide board as an example. Each and every individual board is placed one at a time into the adhesive until the glued area is covered. Once completed, another area is marked and laid.

Not All Types Of Hardwood Should Be Glued

Contrary to what you may hear, not all products can be glued easily. Put another way, gluing solid 3/4" hardwood has always been risky business, but some premium urethane glue manufacturers will warrant their use. The difficulty encountered with solid hardwood is the lack of flexibility compared to more common products that are glued; engineered flooring.

Common types used for gluing down are engineered hardwoods. Thickness vary from 1/4 inch up to 3/4" depending on the manufacturer. During manufacturing the bottom sides of many products are milled with relief cuts. This insures the flooring can bend to minor irregularities in the contour of the subfloor it is being installed, while increasing the bonding contact with adhesive at the same time. This is Relief cuts on backsidedefinitely not an excuse to skip floor preparation; stressed heavily on this site.

Pros and Cons Of Gluing

Most consumers prefer the solid feeling of hardwood floors underfoot. Floating floors for the most part do not offer this benefit unless a premium underlayment is used and a very flat subfloor is maintained prior to installation. After the addition some still complain of the hollow effect floating floors exhibit. A properly glued hardwood floor will feel and sound very much like a traditional solid floor.

Adhesives

Adhesives used for these types of installations do not come by cheaply. More preferred types recommended by many manufacturers can cost upwards of eighty cents a square foot depending on where it is purchased. With any glue down installation, do not take the suggestion of ill informed persons that any old glue will work while saving you bunches in the same breath. Skimping on costs in this department may very well lead you to our message board forum titled, "Yikes I Have Problems."

How Long Does It Take To Install? Are Adhesives Toxic?

Assuming you have a 400 square foot, square room with furniture moved and everything is ready to go, one experienced installer can complete a 3 inch wide glue down installation in 10 -12 hours. Adhesives used today are predominantly three types. Water based, urethane based, or acrylic, with the majority of manufacturers leaning towards the urethane.

Older more toxic adhesives are long gone, with newer more environmentally friendly varieties. If you are chemically sensitive it may be wise to vacate the premises when work is being done. With glue downs, curing time is typically one day or an overnight period before furniture can be moved back into place.

Costs Involved On Our Job

CostsIn this glue down segment the product used was an prefinished engineered three and one quarter inch wide plank manufactured by Lauzon. Total square footage tallied to 1,250 which was purchased direct over the internet from Hoskinghardwood.com to a customer in the Jacksonville, Florida area.

Other materials used on the job included adhesive purchased in five gallon containers. Spread rates for the adhesive came in at 45 square feet per gallon (using Bostik#8 flat V-notch trowel) which translates to 5.5 containers. What is not included on this job is moisture protection. Considering the job itself took place in 2003, concrete slab sealers were not widely used or even recommended.¹

Preparation

Preparation on the job consisted of scraping the entire concrete sub floor with a hand held four inch scraper. Also about 200 pounds of floor leveling compound was used to fill low spots. Typically concrete scraping is included in the installation rate, unless conditions are severe; not this case.

Additionally, installers often factor in minor floor prep into the going installation labor rate. What constitutes minor? Professionals will vary, but anything over a half hour generally calls for additional costs. On this job three hours were billed at the rate of $60.00 per hour. Materials added another $ 170.00 to the bill.

Trim Moldings

The only pre finished trim moldings used on this job consisted of t-moldings to be used at connecting tiled areas of four small door openings in the 28 to 36 inch range and two larger areas. Total lineal footage on this molding equaled 35 feet. With the Lauzon specs at 6’6” per t-molding, six pieces came with the order.

The customer preferred painted white shoe molding on the job that amounted to 345 lineal feet. Supplied by the customer at their cost of 25 cents per lineal foot. Installation labor for the shoe came in at $1.25 per lineal foot.

Others

Considering this was new construction no existing floor removal was necessary. The customer also took care of all waste disposal.

Breakdown Of Costs - Today 2015

Description
Cost/Rate
Quantity
Total
Material Hardwood (S/F)
$ 6.87
1,250
$ 8,587.50
Material Adhesive
179.99
6
1,079.94
Material T Moldings (each)
58.00
6
348.00
Material Shoe Molding (L/F)
.25
345
86.25
Material Floor Leveling
170.00
1
170.00
Installation Labor Floor (S/F)
3.25
1,250
4,062.50
Installation Labor T Moldings (L/F)
1.25
36
45.00
Installation Labor Shoe Moldings (L/F)
1.25
345
431.25
Floor Preparation Labor (hour)
60.00
3
180.00
Total
$ 14,990.44

S/F- Square Feet
L/F- Lineal Feet

¹ - Today (2015) many installers opt for multiuse adhesives that offer both moisture protection and adhesive. Some names include Mapei Ultrabond ECO® 995, Bostik Bostik Ultra-Set SingleStep and Taylor MS-Plus Advance.

Go To: 3" Plank Glue Down Job Go to Tips, precautions & procedures on this jobsite.