Dow Styrofoam

The Value of Residing With STYROFOAM™ Brand XPS Insulation

Residing is a great opportunity to increase a home’s value with a fresh, new look. It’s also an opportunity to increase energy efficiency and overall comfort with moisture-resistant, durable insulation.

For 60 years, BLUE™ STYROFOAM™ Brand Insulation has been a leading building insulation solution for residing contractors and homeowners alike. STYROFOAM™ Brand Extruded Polystyrene (XPS, ASTM C578 Type X) Insulation is valued for its exceptional insulation performance, excellent moisture resistance and the appropriate level of water vapor permeability under vinyl siding.

To appreciate the value of Dow’s extensive portfolio of rigid insulated sheathings, Dow recommends comparison shopping STYROFOAM™ Brand XPS and the competition – white bead board or expanded polystyrene (EPS, ASTM C578 Type I).

As part of a Type I foam-backed vinyl siding system, EPS is laminated or adhered to vinyl siding for ease of installation. When comparing STYROFOAM™ Brand XPS to this system, it is important to consider the following characteristics, including:

  •  Foam structure
  •  Compressive strength
  •  Thermal performance
  •  Moisture resistance
  •  Breathability
  •  Ability to block air infiltration

After you have learned more about – and compared – the key components of quality insulation, you will be in a better position to choose the right insulation for your application.

Visual Comparison

The first comparison is simple. STYROFOAM™ Brand XPS is BLUE™. EPS is white. Then when you look under a microscope, it is easy to see the structural difference.


Proprietary formulations and manufacturing processes for STYROFOAM™ Brand XPS ensures a closed-cell, high-density structure, providing a compressive strength of 15 psi (ASTM C578 Type X). This means XPS stands up to pressure and abuse at the job site much better than white EPS, with a compressive strength of 10 psi (ASTM C578 Type I).

STYROFOAM™ Brand XPS also resists moisture and maintains R-value.

When the white EPS backing on vinyl siding becomes damaged, it can create gaps, which can increase the risk of water absorption. Moisture absorption significantly impacts the R-value, reducing the overall energy efficiency and performance of the EPS-backed siding. The excess moisture can also increase the risk of mold and mildew and other moisture-related problems.



Proof in Numbers

STYROFOAM™ Brand XPS Insulation is built on sound scientific principles and the proof is in the test results. Insulation from Dow outperforms white bead board in the following categories based on ASTM C578.




The Value of Science

When it comes to R-value, the greater the number the better. BLUE™ STYROFOAM™ Brand XPS not only starts off with a greater value (5.0 per 1"), but its durable formulation and consistent thickness provide a long-term, stable R-value on the walls of a home. In contrast, EPS Type I has an R-value of 3.6 per 1".

Contoured vinyl siding adhered to contoured white bead board (EPS) may be a time-saver, but it comes at a cost: Contoured EPS foam has a significantly lower Rvalue when compared to the consistent thickness found in STYROFOAM™ Brand Extruded Polystyrene Insulation. For the best value, you cannot beat STYROFOAM™ Brand XPS for consistent and continuous protection around a building envelope.


White bead board (EPS, ASTM C578 Type I) absorbs 13 times more moisture than STYROFOAM™ Brand XPS Insulation. Water retention can rob the insulation of R-value and provide the necessary elements for moisture-related problems such as mold and mildew.

Help keep damaging moisture out of a home with STYROFOAM™ Brand XPS.



Let Moisture Escape

What happens when moisture, vapor and bulk water make their way into the siding/insulation system? If water in any form becomes trapped, it can potentially lead to mold, mildew and other moisture-related problems.

In a typical vinyl siding/adhered EPS system, water can become trapped on the one side by the vinyl siding. The only way out in this system is for the water to make its way into the EPS. And this EPS foam is typically applied directly against a relatively impermeable woodbased sheathing, increasing the potential for moisture damage.

As a separate layer, STYROFOAM™ Brand XPS provides an effective air space, which creates a drainage plane that allows water to drain to the bottom of the walls and escape from the building envelope through weep holes. This air space enhances the wall assembly’s drying potential, which can contribute to a more comfortable home and reduce the potential for moisture-related problems.




Think of permeability as a building material’s ability to breathe (allowing moisture in the vapor state to pass through the material). EPS seems to have a higher permeability (5 perms at 1" thick), but when attached to vinyl siding the overall perm rating drops to 0.05. And drying toward the interior is also limited because the typical wood-based sheathing has a perm rating of 0.88.

Bottom line – When looking at an EPSbacked system, the permeability of the overall offering is determined by the siding itself, not the EPS. Therefore, both XPS and EPS-backed vinyl siding systems have similar, if not identical, overall permeability ratings.


Stop Air Infiltration

Air infiltration is one of a home’s biggest enemies. It enters a home throughcountless gaps and cracks, contributing up to 40 percent of a home’s energy loss. That means a typical 2,500 ft2 home can have over 1/2 mile of gaps and cracks.* And to make matters worse, air infiltration also increases the likelihood of moisture intrusion in the form of water vapor.

It takes a WRB to reduce moisture and air intrusion. Several STYROFOAM™ Brand Extruded Polystyrene Insulation products qualify as a WRB, eliminating the need for a separate housewrap, and saving material and installation costs.

White EPS products, however, require a facer with a low perm rating or a separate housewrap with taped seams to claim WRB properties. This adds time, money and material to the bottom line.


WRB Solutions

When installed properly, nearly all rigid foam insulations from Dow qualify as a WRB according to the International Residential Code. Examples include:

  •  STYROFOAM™ Brand DURAMATE™ Insulation – Plus
  •  STYROFOAM™ Brand Insulation – Tongue and Groove
  •  STYROFOAM™ Brand Insulation – Residential Sheathing
  •  STYROFOAM™ Brand Insulation – Residing Board
  •  STYROFOAM™ Brand Insulation – Square Edge
  •  STYROFOAM™ Brand Insulation – HPU


Enhanced Protection

For the highest level of protection against moisture and air infiltration, select from Dow’s extensive portfolio, including:

  •  STYROFOAM™ Brand Extruded Polystyrene Insulation
  •  Dow polyisocyanurate insulation
  •  STYROFOAM™ Brand Spray Polyurethane Foam (SPF) Insulation – RS
  •  WEATHERMATE™ Housewraps
  •  WEATHERMATE™ Straight and Flexible Flashings
  •  WEATHERMATE™ Sill Pan
  •  FROTH-PAK™ FS Foam Insulation Kits and FROTH-PAK™ Foam Sealant Kits
  •  GREAT STUFF PRO™ Gaps & Cracks Insulating Foam Sealant**
  •  GREAT STUFF PRO™ Window & Door Insulating Foam Sealant**
  •  DOW™ Window & Door 1000 Sealant



Projects List

URSA Brand Insulation Board
Project Reference in Malaysia 

1 Dayabumi Complex, KL 2 Happy Garden - Jln Kelang Lama, KL
3 East Asiatic Extension - KL 4 Sabah Hotel - Sandakan, Sabah
5 UDA Shopping Centre - KL 6 Corner P3 Factory - Prai, Penang
7 Ridgo Royal Hotel - Miri, Sarawak 8 D'mayang Apartments - Jln Damai, KL
9 Sucasa Service Apartments - Jln Ampang, KL 10 Telekom - Jln Tun Sambathan, KL
11 Wisma Cyclecarry - Jln Raja Laut, KL 12 The Forum - Jln Tun Razak. KL
13 Capital Square - Jln Munshi Abdullah, KL 14 Condominium - Johor Bahru
15 EON Headquarters - Shah Alam 16 Hotel Syuen - Ipoh
17 Wisma AIA - Melaka 18 Wisma EAC - Jln Tandang, PJ
19 Wisma Guan Aik Mong - Jln 225, PJ 20 Condominium - Bukit Tunku, KL
21 Plaza Raja Chulan - Jln Raja Chulan, KL 22 UOA Centre - Jln Pinang, KL
23 Wisma Kewalram - Jln Ampang, KL 24 Ethylene (M) Sdn Bhd - Kerteh
25 Hospital TLDM, Lumut 26 Maybank Headquarter - Shah Alam
27 Nasteel Electronic (M) Sdn Bhd 28 Pink Rose Kindergarden, USJ
29 Sapura Office - Bangi 30 Southern Hospital, Melaka
31 Wisma Nam Heng - Bukit Mertajam 32 Measat Satelit Building - Langkawi
33 Renaissance Hotel - Jln Ampang, KL 34 Nikko Hotel - Jln Ampang, KL
35 New World Hotel - Jln Ampang, KL 36 Tanaka Electronics Kawasan Perusahaan Bayan Lepas - Penang
37 Kuala Lumpur City Centre Tower 1 & 2 - KL 38 Wisma Perkasa - KL
39 Tropicana Gold Resort - KL 40 Skyline Tower - Johor Bahru
41 D'Parade Condominium - Prai, Penang 42 Marina bay - Tanjong Tokong, Penang
43 Johor Water Front 44 Johor Duty Free Port
45 First Silicon Kuching 46 Kulim Technology Park
47 Prestint 20 Putrajaya 48 Putrajaya Prestint 1, Parcel E
49 Putrajaya 4G1 and 4G2 50 Serdang Hospital
51 Putrajaya Parcel E, LEO Building from Ministry of Energy 52 Putrajaya Parcel Z
53 Data Centre Cyberjaya 54 The Curve, Mutiara Damansara
55 Sri Maya Condominium 56 Emerald Condominium
57 The Curve Hotel 58 KUTKM, Melaka
59 Federal Hill Development Project 60 Bukit Gita Bayu Bungalow
61 Muar Pharmacy, Johor 62 Armanee Shoplot, Mutiara Perdana, Phase 1
63 Shell Refinery Centre, Port Dickson 64 Johson Medical Cabin
65 UTP Mosque 66 Orion Condominium, Jln Tun Razak
67 Damai 33 Town House, KL 68 KLCC Hotel, KL
69 Sri Lanka Airport 70 Cooling Tank
71 Gypsum Factory, Klang 72 SPPK Doble Storey Link House, Cheras
73 CIQ, Johor Bahru 74 Boutique Hotel, Langkawi
75 Dua Residency Condo, Jln Tun Razak 76 Japan Club, Taman Seputeh
77 Sri Maya Condominium - Phase 2 78 Armanee Shoplot, Mutiara Perdana, Phase 2
79 Sarawak International Medical Centre 80 Presint 18, Pangsapuri Kerajaan, Putrajaya
81 3m2, Old Klang Road, KL 82 K Residence, Sky Bridge
83 Pusat Tenaga Nasional, Bangi 84 Langkawi Yacht
85 K Residence, Podium 86 Park & Ride, Putrajaya
87 Great Eastern Condo, Jalan Ampang 88 Pavillion Shopping Centre, KL
89 Mines Heritage, Seri Kembangan 90 Novozymes Research Office, Technology Park
91 KUTKM, Package 2A, Melaka 92 Cargill Palm Product Factory, Port Klang
93 The Meritz Condominium, Jalan Ampang 94 Prefab Housing Project @ TAR Villas, Taman TAR, Ampang
95 D'Alamanda Pudu Impian Condominium, Jalan Pudu Ulu, KL 96 Isetan, Mid Valley
97 Mukim Batu Condo, Mon't Kiara 98 Hampshire 2 Condo, Megan Avenue, KL
99 Plus HQ, Shah Alam 100 Cobrain HQ, Glenmarie Shah Alam
101 Utem, Unit Pentadbiran Utam, Melaka 102 MLNG Sub Station, Bintulu
103 PJ City, Jalan 222, PJ 104 Green Heights Conda, Kuching, Sarawak
105 Park Seven Condo, Persiaran KLCC 106 Suncity Condo, Sri Hartamas
107 UTeM Ayer Keroh, Melaka, Cavity Wall 108 UTeM Ayer Keroh, Melaka, Pusat Komputer
109 UTeM Ayer Keroh, Melaka, Dewan Besar 110 Tunku Abdul Rahman (TAR) College, Setapak
111 D'Alamanda Pudu Impian Condominium, Jalan Pudu Ulu, KL - Phase 2 112 4G7, Jabatan Penguam Negara, Putrajaya
113 Tesco Hypermarket, Kampar, Perak 114 Gurney Plaza Extension, Penang
115 Eco-Paradise Sauna Room Insulation, M'sia 116 Swiss Embassy, KL
117 Ken Bangsar Condominium, KL 118 Hamshire Residence, Off Jalan Amapng, KL
119 ICT Centre, Bank Negara, Cyberjaya 120 ICON (Star Residence) Jln. Tun Razak, KL
121 Titiwangsa Bungalow Project, KL 122 KL Sentral, Tower B & C
123 Country Heights Damansara Bungalow Project 124 F & N Factory, Sg. Besi
125 5G2 Tourism, Putrajaya 126 Lumina Kiara Condominium & Semi-D Project, Mon't Kiara
127 Casuarina / Hard Rock Hotel, Penang 128 Bukit Damansara Bungalow Project
129 Bukit Aman Head Quarter, , KL 130 Tropicana City Office Tower & Pool Deck
131 191 units Sering Ukay Terrace House 132 Perwira Bintang Mall, Melaka
133 Suruhanjaya Tenaga, Precint 2C15, Putrajaya 134 PJ Commercial Development at Sec. 39, SS2, PJ
135 Troika KLCC Condo, KL 136 Malaysia Science University (MSU), Shah Alam
137 Senai Airport, JB 138 Gateway Kiaramas Shop & Service Apartment, Mon't Kiara
139 DIGI Telecommunication, Subang Hi-Tech Park 140 Sunway South Quay, Package RC 8
141 Seni Main (K4) Condominium, Mon't Kiara 142 Swiss Residency, Jalan Pudu, KL
143 Bangsar, Jalan Kaloi Condominium 144 34 units 3 storey T/Hse, Valencia, Sg. Buluh
145 Sinaran TTDI Condominium, TTDI, KL 146 Plenitude 197 units D/S Link House, Puchong
147 3 unit Bungalow, Bukit Pantai,Bangsar 148 Sarawak Energy Berhad Building
149 Star Office, Ipoh 150 Universiti Malaya, Komplek Inst. Pengurusan, Penyelidikan & Perundingan
151 Arena Merdu Retail & Office Building, Jln Ampang, KL 152 The Atmosphere Shop & Office, Seri Kembangan (Phase 1)
153 Setia City Mall, Setia Alam, Selangor 154 Sabah Medical Centre - OT Room
155 Gardenview Residence, Cyberjaya 156 Region Asset Factory, Glenmarie
157 Bank Negara Children Care Centre, Jln Ismail, KL 158 Safira @ Subang Bestari - 43 units Bungalow, Sg. Buluh
159 Boulevard Plaza, 3C7, Precint 3, Putrajaya 160 Weida Base Slab Insulation, Kuching, Sarawak
161 Denai Alam 2 & 3 storey Terrace House, Sg. Buluh 162 Merdeka Plaza, Kuching
163 KTMB Passanger Platform, Gurun, Alor Star 164 5 Stone Condominium, SS 2, PJ
165 Biogas & Wastewater Treatment Plant (12 units Treatment Tanks) for Livestock, Samarahan, Sarawak 166 The Atmosphere Shop & Office, Seri Kembangan (Phase 2)
167 Monnash Universit, Graduate School, Sunway 168 Tokuyama M'sia Polycrstalline Mfgt. Plant, Bintulu, Sarawak (Phase 1)
169 KL Sentral, Lot G 170 Primo II - 31 units Bungalow, Bukit Jelutong, Shah Alam
171 Viva Hotel, Jln Loke Yew, KL 172 Elken Factory, Subang UEP Industrial Park, Subang Jaya
173 WismaMiramas Office Building, Taman Desa, Old Klang Road 174 Sunway Montana 107 units Terrace House & Semi-D, Desa Melawati, KL
175 Bungalow RS1 & RS2, Taman Emas, Dengkil, Sepang 176 Ken Holding Corporate Office Chiller Tank, TTDI, KL
177 Eco City, Midvalley - Sales Gallery 178 CIQ Ferry Terminal Nusajaya, Johor Bahru
179 NAZA TTDI Mosque, Seksyen 15, Shah Alam 180 U-Thant Residency, KL
181 Tropica Grande, Tropicana PJ 182 The Strand Garden Office, Kota Damansara
183 Tokuyama M'sia Polycrstalline Mfgt. Plant, Bintulu, Sarawak (Phase 2) 184 Refurbishment of Dayabumi Complex, KL (Raised Floor)
185 Akashi Kikai Factory, Labu, Seremban 186 Sunway South Quay, Package RC 3
187 Eco-Paradise Sauna Room Insulation, Singapore 188 Tune Hotel Extention, Jln Tunku Abdul Rahman, KL
189 Sunway Monash University Extension, Bandar Sunway 190 Jaya One (Phase 3), Petaling Jaya - Raised Floor Insulation
191 Jaya One (Phase 3), Petaling Jaya - Metal Deck Roof Insulation 192 Cherish Spring Office Suit & Service Apartment, Seksyen 13, Shah Alam
193 Molek Pine Condominium, Taman Molek, Johor 194 Ice Truck, Nilai
195 TTDI Adina, Shah Alam 196 Glenmarie Court Bungalow, Shah Alam
197 Madge Mansions Luxury Condominium, Jalan Ampang 198 Comtec Solar Water Plant, Kuching
199 Alamanda Surau (Raised Floor), Putrajaya 200 Indo Alam Bina Development
201 Ritz Corporate Suite, Jalan Ampang 202 Tangkas Arena L/Industrial Development, Subang Jaya
203 AraGreens Residences, Ara Damansara 204 9 Madge Luxury Low Density Service Apartment, Jln Ampang, KL
205 Sunway University, Bandar sunway (New Phase) 206 The Capers Sentul East (Club House), KL
207 Ice Truck, Nilai (Chemrex Corporation S/B) 208 Biz Suites, Kota Damansara
209 Zefer Hill Residence, Bandar Kinrara, Puchong 210 Ice Truck (Extruded Polystyrene Foam Insulation S/B)
211 Glenteq Singpore 212 The Leafz, Sungei Besi, KL
213 Plaza Merdeka, Kuching, Sarawak 214 The Light Collection, Penang
215 Hydroelectro Plant, Hulu Terengganu 216 B. Braun Factory (5, 8 & 9), Bayan Lepas, Penang
217 Rimbun Condominium, Ampang Hilir, KL 218 Kiatthanavat Bangkok
219 Show House at Old Klang Road 220 Mid Valley Megamal (Raised Floor)
221 Y-Cantonments TownHouse, Pulau Tikus 222 Eve Suite, Ara Damansara
223 DYMM Sultan Selangor Residence, Bukit Jelutong, Shah Alam 224 Damansara City, Pusat Bandar Damansara, KL
225 BEREMI Hotel, Off Jalan Sultan Ismail, KL 226 Cyberjaya Green Mosque, Cyberjaya
227 Seri Riana Resudence, Wangsa Maju, KL 228 Jade Hills, Kajang
229 Sentral Bazar, Nilai 230 Ritz Corporate Suite (Tower 2), Jalan Ampang
231 Xiamen University, Sepang 232 B. Braun CGMP Plant Phase 2 (Package B1A), Bayan Lepas, Penang
233 Tropicana Gardens (Phase 1), Kota Damansara 234 Mid Valley Megamal (Raised Floor - Package: T-006 & T006A, 3rd Flr)
235 University Technology Petronas (UTP), Tronoh, Ipoh - R & D Block 236 Melaka Hatten City - Lot 8, Melaka
237 Samalaju Port (New Phase), Bintulu 238 Pavilion Bukit Bintang (New Phase)
239 Tropicana Gardens (Phase 2), Kota Damansara 240 Royal Pavilion Bukit Bintang, KL
241 Pantai Sentral Park, Pantai Dalam , KL 242 Petrajaya Hospital, Kuching, Sarawak
243 The Armanna Service Apartment, Kemuning Utama, Shah Alam 244 Site Project SPE DUKE 3 (Sec 2) - CAISSON PILE