Great all around
RVMattress.comSignature Hybrid
- Hybrid
- 13.25 in thick
- Soft / Medium / Firm
Sleep Foundation: Best Mattress Overall Read review
$1,865RV King - 70x80 · list priceSee price
Grand Design Transcend 315RKT mattress size
Main bed70 × 80 inRV king
That's an RV king, 6 in narrower than a regular king (76 × 80 in). A regular king won't fit, so get an RV king in exactly 70 × 80 in.
About the RV king size →Grand Design spec sheet, 2027.
Mattresses in 70 × 80 in
We may earn a commission when you buy through some of these links. It doesn't change which mattresses we list.
Best value
RVMattress.comCopperFlex Essential
- All-foam
- 6 in thick
- five comfort options
$799RV King - 70x80 · list priceSee price
Firm
RVMattress.comPlank Firm Luxe
- Hybrid
- 13 in thick
- Firm / Extra Firm
$1,865RV King - 70x80 · list priceSee price
Cooling
RVMattress.comAurora Luxe Cooling
- Hybrid
- 13.25 in thick
- Soft / Medium / Firm
Sleep Foundation: Best Mattress for Temperature Regulation Read review
$2,465RV King - 70x80 · list priceSee price
RV hybrid
RVMattress.comCopperFlex RV Hybrid
- Hybrid
- 10 in thick
- Medium-Firm
$1,065RV King - 70x80 · list priceSee price
Custom size
Mattress InsiderLuxury Gel Memory Foam
- Memory foam
- 8 in thick
- not stated
Made to 70 × 80 inGet a quote
The Transcend bedroom. Measure the platform, not the old mattress, before you buy.
Bed sizes by year
| Year | Main bed | Bunks | Other beds | Source |
|---|---|---|---|---|
| 2025 | 70 × 80 in King | – | – | Grand Design spec sheet |
| 2026 | 70 × 80 in King | – | – | Grand Design 2026 model-year brochure |
| 2026 | 70 × 80 in King | – | – | Grand Design spec sheet |
| 2027 | 70 × 80 in King | – | – | Grand Design spec sheet |
Years not listed weren't published.
The 315RKT floorplan
Grand Design's 2027 315RKT floorplan.
Is this your 315RKT?
Check the year and length against your RV before you order.
| Year | Model | Length | Sleeps |
|---|---|---|---|
| 2025 | Transcend 315RKT | 36' 10" | 4 |
| 2026 | Transcend 315RKT | 36' 10" | 4 |
| 2027 | Transcend 315RKT | 36' 10" | 4 |
Other Transcend mattress sizes
Sources
- Grand Design (granddesignrv.com), archived copy: https://web.archive.org/web/20250514084208/https://www.granddesignrv.com/travel-trailers/transcend/315rkt
- Grand Design (granddesignrv.com), archived copy: https://web.archive.org/web/20260510083514/https://www.granddesignrv.com/travel-trailers/transcend/315rkt
- Grand Design (granddesignrv.com): https://www.granddesignrv.com/travel-trailers/transcend/315rkt
Questions
What size mattress is in the Grand Design Transcend 315RKT?
The main bed is 70 × 80 in (Grand Design spec sheet, 2027).