Continuing

Education

Services

1

Designing Concrete Masonry Walls

to Resist Moisture Penetration Program #: 0508-01 NCMA

Continuing

Education

Services

2

This program is registered with the AIA/CES for

continuing professional education. As such, it does not

include content that may be deemed or construed to be an

approval or endorsement by the AIA of any material of

construction or any method or manner of handling, using,

distributing, or dealing in any material or product.

Questions related to specific materials, methods, and

services will be addressed at the conclusion of this

presentation.

AIA Disclaimer Notice

Continuing

Education

Services

3

Satisfying the Owner

Continuing

Education

Services

Associated Effects of

Moisture

• Efflorescence

• Corrosion of Metals &

Reinforcement

• Staining / Mold / Mildew

• Leaks

• Rotting & Degradation of Insulation

Continuing

Education

Services

5

Keys to Providing

Moisture Penetration Resistance

• Quality Materials

• Good Construction

– following specifications

– full head joints

• Proper Detailing and Specifying

– locations of flashing, weeps, etc..

– back-up systems

Continuing

Education

Services

Concrete Masonry Units

• ASTM C 90 Properties

– Compressive Strength

– Absorption

– Dimensional Tolerances

– Density Definitions

– Linear Drying Shrinkage

Continuing

Education

Services • Unit Properties Not in C 90

– Color

– Texture

– Density

– Water Repellency

– Fire Ratings

– Thermal Properties

– Sound Properties

Concrete Masonry Units

Continuing

Education

Services

8

Masonry Mortars

• Specify ASTM C 270

• Mortar Options:

– Portland Cement and Lime

– Masonry Cement

– Mortar Cement

• Mortar Types: M, S, N, and O

• Mortar Quality Control

Continuing

Education

Services

9

Products & Workmanship

• The quality and compatibility of material

components and care in installation are key to

wall performance.

• The recommended specification for products

and workmanship for masonry construction are

covered in the latest editions of:

Masonry Standards Joint Committee

ACI 530.1 / ASCE 6 / TMS 602

Continuing

Education

Services

10

The Role of the Architect

• Design, Detailing and Specifying

Continuing

Education

Services

Components for Mitigation

• Flashing

• Weeps

• Vents

• Water Repellent Admixtures

• Sealants & Coatings

• Vapor Retarders

Continuing

Education

Services

Good Performance

Requires...

• Flashing

• Weeps

• Vents

• Water Repellent Admixtures

• Sealants & Coatings

• Vapor Barriers

Integration of

ALL

Components

Continuing

Education

Services

Masonry Barrier Wall Types

• Solid Wall

– Solid grouted single-wythe

– Solid grouted composite cavity

• Multi-Wythe Drainage Wall

– Veneer

– Noncomposite cavity

• Single-Wythe Drainage Wall

– Ungrouted

– Partially grouted

Continuing

Education

Services

14

The Solid Wall

1 Grout fill

2 Finish Sealed and

integral repellent

3 Mortar Integral repellent

Continuing

Education

Services

15

1

2

3

4

5

6 Multi-Wythe

Drainage Wall

1 Unit concrete

2 Vertical air

space

3 Mortar and

masonry

veneer

4 Flashing

5 Weep holes

6 Vents

Continuing

Education

Services

16

4

3

1

2

5 Single Wythe

Drainage Wall

1. Unit Concrete

Masonry sealed

and/or integral

repellent

2. Mortar

3. Through Wall

Flashing

4. Weep Holes

5. Vents

Continuing

Education

Services Level of

Defense

1

2

3

Surface Protection

•Tooling of Mortar Joints

• Sealants /Coatings

Internal Protection

• Integral Water Repellents

Drainage

• Flashing, weeps and vents

Defense Mechanism

Best Performance Is

Achieved By Redundancy

Continuing

Education

Services

Weather Resistant Mortar Joints

Concave joint

(preferred)"V" joint

Continuing

Education

Services

19

Full Thickness of

Mortar Joints

f

Properly mortared

ft

head jointInadequate

head joint

Thickness no lessthan t

Continuing

Education

Services

20

Clear Film Treatments Acrylics - form elastic film over surface. Quick drying. $

Penetrating Repellents (Silicones) Silicone Resins - good penetration. Drying time 4-5 hours. $

Silanes - good penetration. More volatile (quick evaporation).

Can be applied to damp surfaces. $$

Siloxanes - similar benefits of silanes. Effective on wider

variety of surfaces. $$

Others

Water Based

Solvent Based

Clear Surface Treatment

Repellents

Continuing

Education

Services

21

Other Surface Treatments

Cementitious Coatings Portland Cement Plaster (Stucco) $$

Paints

Cement-Based - good durability (including alkalis). Fills

small voids. Apply to damp surface and damp cure. $

Latex - water based. Good durability (including alkalis). Breathable. Applied to damp or dry surfaces and cure quickly. Good hiding characteristics. Easy application - brush, roller, spray. $

Alkyd Paints - Durable, flexible, gloss retention, quick

dry.Low alkali resistance. Hard to brush apply. $

Continuing

Education

Services

22

Surface Barrier Limitations

If the surface barrier is compromised,

moisture can move through the wall by:

• gravity

• pressure

• capillary action

Integral Water

Repellent admixtures

inhibit capillary action

Continuing

Education

Services

23

Integral Water Repellents

• Polymeric material which does not alter

the finished appearance of the block

• Lasts the lifetime of the unit

• Cuts down on possibility of efflorescence

• Incorporate a compatible integral water

repellent admixture into the mortar

Continuing

Education

Services

Vapor Barrier

Rigid Insulation

Wall Finish

Wall Flashing

Weeps @

32”o.c.

Water Repellent

Admixture

Horizontal

Reinforcement

Surface

Coating

Z-Furring

&

Fasteners

Vertical

Reinforcement

Section

Detail at

Base of

Single Wythe

Wall

Continuing

Education

Services

25

Flashing Material Options

• Sheet Metals

• Composite Materials

• Plastic and Rubber Compounds

Continuing

Education

Services

Stainless Steel

Cold-Rolled Copper

Galvanized Steel

Durable,

non staining

Flexible, durable,

easily formed and

joined

Easy to paint and

durable

Hard to form

Damaged by excessive

flexing and can stain

Corrodes early in acidic

and salty air

Material Advantages Disadvantages

Flashing Materials

Sheet Metals

Continuing

Education

Services

Lead-coated copper

Copper laminates

Flexible, durable,

non-staining

Easy to form

Difficult to seal joints,

damaged by excessive

flexing, metal drip edge

suggested

Degrades in UV light,

more easily torn than

metal

Material Advantages Disadvantages

Flashing Materials

Composites

Continuing

Education

Services

EPDM

Rubberized

asphalt

PVC

Flexible, easy to form,

non-staining

Fully adhered, separate lap adhesive not needed, self healing, flexible, easy to form and join

Easy to form and join,

non-staining, low cost

Aesthetics if not used with a

metal drip edge, full support

recommended

Full support required, degrades in UV light, metal drip edge required

Easily damaged, full

support required, metal drip

edge required, questionable

durability

Material Advantages Disadvantages

Flashing Materials

Plastics and Rubber Compounds

Continuing

Education

Services

Splices

4”

Continuing

Education

Services

Splicing Metal Flashing

Metal Flashing 4 in. (102 mm)

lap min.

gap in flashing

/ in. (64 mm)1

4 Fully adhere

membrane

Membrane

Metal Flashing

Step 1 Step 2

Splice Cross Section

Continuing

Education

Services

• Cotton sash

cord for

drainage path

(remove after

wall is laid up)

• Partially open

head joints

(preferred)

Weeps

Continuing

Education

Services

32

Flashing Locations

Needed anywhere the downward

vertical path of water to the weeps

is interrupted:

• base and foundation

• lintels

• bond beams

• parapets

• intermediate roofs

Continuing

Education

Services

33

Flashing Detail at

Reinforced Cell

Typical detail at inside of faceshell

b) Unreinforced cell

of washed pea stone. Alt. — leave out every other reduced size facing unit on top of flahing to serve as cleanouts unitl the wall is completed.* Cavity filter is any material used in conjunction with mortar nets to prevent mortar droppings from cloggin the weeps, i.e. filter paper or 2 in. (51 mm)

a) Reinforced cell

off to fit (typ. a & c)and part of webs cut

Cavity filter*

o.c. partially open2 ft. 8 in. (813 mm)Weep holes @

(typ. b & c)

1 in. (25 mm)

joints"L-shaped" head

Architectural unitwith inside faceshell

Edge of flashing

Solid unit or

Cavity filter*

from joint

to support flashingfilled hollow unit

sealed by mortar

1 in.

e) One-piece flashing

d) Two-piece flashing

Bond beam, lintel orfoundation (typ.)

c) Optional unreinforced masonry

4 in. (102 mm) unit

Drip edge (typ.)

48 in. (1219 mm) o.c.#5 (#16) min. @

Mortar net*

(25 mm)

Flashing

inside of faceshellStop flashing at

> 8 in. (203 mm) wall4 in. (102 mm) unit for8 in. (203 mm) wall,3 in. (76 mm) unit for

Continuing

Education

Services

34

Flashing Detail at

Unreinforced Cell

Typical detail at inside of faceshell

b) Unreinforced cell

of washed pea stone. Alt. — leave out every other reduced size facing unit on top of flahing to serve as cleanouts unitl the wall is completed.* Cavity filter is any material used in conjunction with mortar nets to prevent mortar droppings from cloggin the weeps, i.e. filter paper or 2 in. (51 mm)

a) Reinforced cell

off to fit (typ. a & c)and part of webs cut

Cavity filter*

o.c. partially open2 ft. 8 in. (813 mm)Weep holes @

(typ. b & c)

1 in. (25 mm)

joints"L-shaped" head

Architectural unitwith inside faceshell

Edge of flashing

Solid unit or

Cavity filter*

from joint

to support flashingfilled hollow unit

sealed by mortar

1 in.

e) One-piece flashing

d) Two-piece flashing

Bond beam, lintel orfoundation (typ.)

c) Optional unreinforced masonry

4 in. (102 mm) unit

Drip edge (typ.)

48 in. (1219 mm) o.c.#5 (#16) min. @

Mortar net*

(25 mm)

Flashing

inside of faceshellStop flashing at

> 8 in. (203 mm) wall4 in. (102 mm) unit for8 in. (203 mm) wall,3 in. (76 mm) unit for

Continuing

Education

Services

35

Typical Detail at

Inside Face Shell

Typical detail at inside of faceshell

b) Unreinforced cell

of washed pea stone. Alt. — leave out every other reduced size facing unit on top of flahing to serve as cleanouts unitl the wall is completed.* Cavity filter is any material used in conjunction with mortar nets to prevent mortar droppings from cloggin the weeps, i.e. filter paper or 2 in. (51 mm)

a) Reinforced cell

off to fit (typ. a & c)and part of webs cut

Cavity filter*

o.c. partially open2 ft. 8 in. (813 mm)Weep holes @

(typ. b & c)

1 in. (25 mm)

joints"L-shaped" head

Architectural unitwith inside faceshell

Edge of flashing

Solid unit or

Cavity filter*

from joint

to support flashingfilled hollow unit

sealed by mortar

1 in.

e) One-piece flashing

d) Two-piece flashing

Bond beam, lintel orfoundation (typ.)

c) Optional unreinforced masonry

4 in. (102 mm) unit

Drip edge (typ.)

48 in. (1219 mm) o.c.#5 (#16) min. @

Mortar net*

(25 mm)

Flashing

inside of faceshellStop flashing at

> 8 in. (203 mm) wall4 in. (102 mm) unit for8 in. (203 mm) wall,3 in. (76 mm) unit for

Continuing

Education

Services

36

Typical detail at inside of faceshell

b) Unreinforced cell

of washed pea stone. Alt. — leave out every other reduced size facing unit on top of flahing to serve as cleanouts unitl the wall is completed.* Cavity filter is any material used in conjunction with mortar nets to prevent mortar droppings from cloggin the weeps, i.e. filter paper or 2 in. (51 mm)

a) Reinforced cell

off to fit (typ. a & c)and part of webs cut

Cavity filter*

o.c. partially open2 ft. 8 in. (813 mm)Weep holes @

(typ. b & c)

1 in. (25 mm)

joints"L-shaped" head

Architectural unitwith inside faceshell

Edge of flashing

Solid unit or

Cavity filter*

from joint

to support flashingfilled hollow unit

sealed by mortar

1 in.

e) One-piece flashing

d) Two-piece flashing

Bond beam, lintel orfoundation (typ.)

c) Optional unreinforced masonry

4 in. (102 mm) unit

Drip edge (typ.)

48 in. (1219 mm) o.c.#5 (#16) min. @

Mortar net*

(25 mm)

Flashing

inside of faceshellStop flashing at

> 8 in. (203 mm) wall4 in. (102 mm) unit for8 in. (203 mm) wall,3 in. (76 mm) unit for

Optional Flashing Detail at

Unreinforced Cell

Continuing

Education

Services

Copings and

Caps

Continuing

Education

Services

Insulation

Flashing

Reglet

Solid

Sealant

Wall Flashing

Drip

Bond Beam

Horizontal

Reinforcing

Weeps @

16”o.c.

Rake & Caulk

Solid

Water

repellent

Ad-Mixture

Drip

Insulation

Vapor Barrier

Wall Finish

Coping and

Parapet Detail

Standard

Continuing

Education

Services

39

Great Performance!!

When proper detailing is combined with

good materials and good construction -

masonry provides excellent protection

against water penetration.

Please call us if you need more information

about how to construct a water-tight

structure.

NCMA