Any time you require a compact laundry pair, you have different configuration installations available to help save space. One option is to place the appliances side-by-side like larger conventional laundry pairs. When placing the appliances side-by-side, you need to make sure there is sufficient clearance for water lines and airflow. No dryer vent is necessary, because the dryer uses ventless drying technology. The minimum clearances are at least one inch at the sides, and four inches behind the unit. Both the washer and dryer have widths of 24 inches, with a maximum depth of 27 inches. Adding in the required clearances would mean your laundry space needs to be at least 31 inches deep and 51 inches wide. In the event you have the required depth, but not the width, the units are stackable.
Stacking a washer and dryer has a combined minimum clearance of 27 inches wide, 31 inches deep, and 67 inches tall. It is recommended to not place anything on top of the dryer once it is stacked. In addition, stacking the appliances requires a stacking kit in order to securely install the dryer on top of the washer. You should not install the dryer without the stacking kit, because it will not remain in place. Further, as both the washer and dryer give off vibrations, the dryer could fall off of the washer unexpectedly, without the proper kit. Stacking kits are sometimes included, depending upon your stackable model, or have to be purchased as an accessory.